Tag Archives: Zero day exploits

CVE-2021-21972 – Kritische Schwachstelle in vSphere Client. Was hätte Peter F. Drucker dazu gesagt?

6. März 2021

Am 23. Februar 2021 veröffentlichte VMware(1) die Schwachstelle CVE-2021-21972(2) im vSphere HTML 5 Client. Bei CVE-2021-21972 handelt es sich um eine kritische Schwachstelle, vergleichbar mit Schwachstelle CVE-2019-19781 im Citrix Application Delivery Controller, die 2020 im Angriff auf die Uni-Klinik Düsseldorf verwendet wurde.

Schwachstelle	CVSS V3 Vektor
Kritische Schwachstelle	AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H	Definition
CVE-2021-21972	AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H	VMware vSphere RCE
CVE-2019-19781	AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H	Citrix Application Delivery Controller RCE, Uni-Klinik Düsseldorf, 2020

Die Ausnutzung einer kritischen Schwachstelle führt zum vollständigen Verlust der Integrität des Systems (I:High), den ich höher bewerte als den vollständigen Verlust der Verfügbarkeit oder der Vertraulichkeit. Der vollständige Verlust der Integrität hat zur Folge, dass der Angreifer unerkannt und unbemerkt beliebige Änderungen am System vorzunehmen. Das kann in der Prozessindustrie, wie das Beispiel Triton(3) zeigt, zu Explosionen führen.

CVE-2021-21972 ist wie CVE-2019-19781 eine Remote-Code-Execution-Schwachstelle. RCE-Schwachstellen ermöglichen dem Angreifer, beliebigen Code im Systemkontext, also mit den höchsten Berechtigungen, auszuführen.

In beiden Fällen ist die Access Complexity AC:Low. Der Angreifer benötigt nur wenig Knowhow zur Durchführung des Angriffs. Steht das betroffene System in der DMZ, so kann prinzipiell jeder der ca. 4 Mrd. Internetteilnehmer mit wenig Aufwand einen Angriff starten und das System übernehmen.

Eine kritische Schwachstelle sollte also umgehend nach ihrer Veröffentlichung gepatcht werden. Ist dies nicht möglich, so sollten direkt risiko-reduzierende Maßnahmen ergriffen werden, um einem Verlust der Integrität vorzubeugen. Sind weder Patches noch risiko-reduzierende Maßnahmen bekannt, so sollte der Zugriff vom Internet auf das betroffene System deaktiviert werden.

vSphere Client-Systeme in Region Kassel, Quelle: Shodan

Im Fall CVE-2019-19781 dauerte die Bereit-stellung des Patches einen Monat. Zudem wurde die Schwachstelle bereits vor der Veröffentlichung in Angriffen genutzt.
CVE-2019-19781 war also ein Zero-Day-
Exploit. Das ist bei CVE-2021-21972 nicht der Fall. VMware(1) veröffentlichte mit der Schwachstelle Patches und Workarounds. Workarounds sind notwendig in der Zeit bis der Patch ausgerollt und aktiviert ist. Damit konnten die ca. 6.500 betroffenen vSphere Clients, die direkt vom Internet erreichbar sind, effizient geschützt werden. Da bereits am Tag nach der Veröffentlichung ein Exploit(4) verfügbar war mussten die Systeme umgehend gepatcht werden. Und IT-Abteilungen haben dies schnell, effizient und mit viel persönlichem Einsatz getan.

Die große Frage ist: Warum sind diese vSphere Client-Systeme überhaupt vom Internet erreichbar? Kritische Systeme wie die Managementsysteme für eine VMware-Infrastruktur sollten nie vom Internet erreichbar sein. Das gilt nicht für den Citrix Application Delivery Controller. Dessen Aufgabe ist die sichere Bereitstellung von internen Ressourcen für Anwender, die vom Internet zugreifen. Im Fall VMware haben wir Probleme geschaffen, die wir bei Veröffentlichung einer neuen Schwachstelle mit großer Effizienz lösen. Hierzu sagt Peter F. Drucker(5):

“There is surely nothing quite so useless as doing with great efficiency what should not be done at all.”

Ist CVE-2021-21972 ein Einzelfall? Leider nicht. Nur zwei Beispiele:

Stand 6.3.2021 listet Shodan 1,265,880 Systeme mit offenem SMB Port, obwohl WannaCry 2017 solche Systeme für den Zugriff auf interne Computernetzwerke nutzte.
Shodan listet 3,974,926 Systeme, die per RDP erreichbar sind, obwohl CVE-2019-0708 (BlueKeep) mit hohem Aufwand weltweit gepatcht wurde um Angriffe von WannaCry-Ausmaßen zu verhindern.

In beiden Fällen müssen wir die Frage stellen: Ist das notwendig? Wie viele IT-Experten, die wir dringend für Digitalisierungsprojekte benötigen, arbeiten an der Lösung von IT-Problemen, die nicht existieren sollten? Können wir uns eine derartige Verschwendung von Expertise leisten?

Peter F. Druckers Veröffentlichung “Managing for Business Effectiveness” aus dem Jahr 1963 ist wieder top aktuell.

Schönes Wochenende.

Quellen

VMSA-2021-0002 [Internet]. VMware. [zitiert 25. Februar 2021]. Verfügbar unter: https://www.vmware.com/security/advisories/VMSA-2021-0002.html
NIST Information Technology Laboratory. NVD – CVE-2021-21972 [Internet]. NIST National Vulnerability Database. 2021 [zitiert 5. März 2021]. Verfügbar unter: https://nvd.nist.gov/vuln/detail/CVE-2021-21972
Sobczak B. SECURITY: The inside story of the world’s most dangerous malware [Internet]. 2019 [zitiert 11. Mai 2019]. Verfügbar unter: https://www.eenews.net/stories/1060123327
Klyuchnikov M. Unauthorized RCE in VMware vCenter [Internet]. PT SWARM. 2021 [zitiert 6. März 2021]. Verfügbar unter: https://swarm.ptsecurity.com/unauth-rce-vmware/
Drucker PF. Managing for Business Effectiveness. Harvard Business Review [Internet]. 1. Mai 1963 [zitiert 6. März 2021]; Verfügbar unter: https://hbr.org/1963/05/managing-for-business-effectiveness

Adobe Flash zero day exploited in the wild. Remote code execution vulnerabilities are hacker’s favorites!

8 December 2018

On December 5th, 2018 Adobe published security bulletin APSB18-41[1] for critical vulnerability CVE-2018-15928 in the widely used Flash Player. Gigamon Applied Threat Research (ATR) reported the vulnerability on November 29th, 2018 to Adobe. They detected the issue some days before while analyzing a malicious word document that was uploaded to VirusTotal from a Ukrainian IP address. For a detailed analysis of the attack and the vulnerability see [2][3].

Successful exploitation of CVE-2018-15928 could lead to Arbitrary Code Execution in the context of the current user. Due to RedHat the CVSS3 Base Metrics is CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H with a CVSS3 Base Score of 8.8.

Zero days are not a rare phenomenon. Between 2013 and 2017[4] about 60% of the exploits were disclosed before the related CVE was published.

For about 20% of vulnerabilities in the NVD exploits are published in the exploit database[5]. Only about 1% of the vulnerabilities are exploited in the wild. Thus CVE-2018-15928 is a really rare event.

Remote code/script execution (RxE) vulnerabilities like CVE-2018-15928 represent about 20% of all vulnerabilities. 43% of the exploits published between 1988 and 2018 are related to RxE vulnerabilities.

Remote Code Execution Vulnerabilities. Data: 1988-2018

RxE Vulnerabilities. Data: 1988-2018

Exploits for Remote Code Execution Vulnerabilities. Data: 1988-2018

Exploits for RxE Vulnerabilities. Data: 1988-2018

About 5% of the RxE vulnerabilities are exploited in the wild.

This means, that RxE vulnerabilities are 5 times more often exploited in the wild then Non-RxE vulnerabilities. They are hacker’s favorites!

What does the mean for our vulnerability management strategy?

The remediation process must be started directly upon publication of an RxE vulnerability in the NVD or the disclosure of an exploit for an RxE in the exploit database.
In scope for the first remediation wave must be at least all systems facing the internet, e.g. workstations, servers in the DMZ or in public clouds.
Gathering intelligence about new vulnerabilities from a plethora of publicly available sources (OSINT) is a time-consuming task. A threat intelligence service can speed-up information gathering and reduces the workload of your IT security staff.
In addition, since remediation takes some time, it makes sense to invest in means for enhancing the resilience of application systems.

Expect the worst and be prepared. Or, to echo Hamlet:

To be, or not to be, that is the question:
Whether ’tis nobler in the mind to suffer
The slings and arrows of outrageous fortune,
Or to take arms against a sea of troubles,
And by opposing, end them? To die: to sleep;

Have a good weekend.

Adobe. Security updates available for Flash Player | APSB18-42 [Internet]. 2018 [cited 2018 Dec 8]. Available from: https://helpx.adobe.com/security/products/flash-player/apsb18-42.html
Gigamon Threat Research Team. Adobe Flash Zero-Day Exploited In the Wild [Internet]. Gigamon ATR Blog. 2018 [cited 2018 Dec 8]. Available from: https://atr-blog.gigamon.com/2018/12/05/adobe-flash-zero-day-exploited-in-the-wild/
Qihoo 360 Advanced Threat Response Team. Operation Poison Needles – APT Group Attacked the Polyclinic of the Presidential Administration of Russia, Exploiting a Zero-day [Internet]. 2018 [cited 2018 Dec 8]. Available from: http://blogs.360.cn/post/PoisonNeedles_CVE-2018-15982_EN.html
Jochem K. About 60% of exploits are published before the CVE. What does this mean for your cyber security strategy? [Internet]. IT Security Matters. 2018 [cited 2018 Dec 8]. Available from: https://klausjochem.me/2018/11/04/about-60-of-exploits-are-published-before-the-cve-what-does-this-mean-for-your-cyber-security-strategy/
Offensive Security. Offensive Security’s Exploit Database Archive [Internet]. Exploit Database. [cited 2018 Nov 4]. Available from: https://www.exploit-db.com/

About 60% of exploits are published before the CVE. What does this mean for your cyber security strategy?

4 November 2018

Some days ago Cisco published a vulnerability CVE-2018-15454[1][2] in software running on their security products Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD). Cisco discovered the flaw while investigating a support case, in other words, the attackers used a zero-day exploit.

How frequent are zero-days? This question is not easy to answer because it takes some time until malicious activity is detected. However, we can compare the date an exploit is published in the Exploit Database[3] with the date the vulnerability is published in the NVD.

Figure 1. Exploit publication date relative to CVE publication date. Data: 2013 – 2017

Between 2013 and 2017 about 60% of the exploits were published before the CVE. With this, about 60% of the exploits are candidates for zero-day exploits.

Figure 2. Exploit publication date relative to CVE publication date details. Data: 2013 – 2017

Figure 2 shows the details within 30 days prior and after the CVE was published.

This is no reason to panic. In general, this means that we should directly start the remediation process once an exploit is published. Do not waste time!

In addition, since remediation takes some time, it makes sense to invest in means enhancing the resilience of application systems. Expect the worst and be prepared.

Find out more in the following posts.

Have a great week.

MITRE. NVD – CVE-2018-15454 [Internet]. 2018 [cited 2018 Nov 3]. Available from: https://nvd.nist.gov/vuln/detail/CVE-2018-15454
Cisco Security. Cisco Adaptive Security Appliance Software and Cisco Firepower Threat Defense Software Denial of Service Vulnerability [Internet]. Cisco Security Advisory. 2018 [cited 2018 Nov 3]. Available from: https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20181031-asaftd-sip-dos
Offensive Security. Offensive Security’s Exploit Database Archive [Internet]. Exploit Database. [cited 2018 Nov 4]. Available from: https://www.exploit-db.com/

To patch or not to patch this is not the question – New Remote Code Execution Vulnerability in Drupal CMS

21 October 2018

Lindsey O’Donnell’s report “Two Critical RCE Bugs Patched in Drupal 7 and 8” [1] published yesterday on Threatpost gives website operators every reason to enter panic mode.

The vulnerabilities are not published in the NIST NVD yet, but Drupal released two security advisories [2] [3] with details.

Why panic? In the past 16 years 177 vulnerabilities [4] related to Drupal were published. That sounds like a lot but consider that 1,075,609 websites were powered with Drupal core in October 2018 [5].

Fortunately, only 13 exploits were published since 2002. On 29 March 2018 the remote code execution vulnerability CVE-2018-7600 (Drupalgeddon2) was published. Within 20 days after publication three exploits were available. Thousands of sites were compromised in the aftermath.

CVE-2018-7602 (Drupalgeddon3) was published on 19 July 2018. In this case exploits were available 81 and 86 days before the CVE was published.

Table: Drupal Exploits since 2010. Click to enlarge.

The table above shows the vulnerabilities with published exploits for the Drupal CMS since 2010. Negative values in column Number of days exploit published after CVE published indicate that the exploit was published before the CVE was published. These are the magic zero-day exploits, the worst-case scenario for website operators because a warning time does not exist.

Except of the green highlighted exploit all exploits were used in the wild, means, they were used in attacks. In addition, except of the green highlighted exploit all CVE were remote code execution or injection vulnerabilities.

For the newly published remote code execution vulnerabilities we can expect

that exploits will be published with a probability of about 7% and
that if exploits are published, they will be published before or at the day the CVE is published.

With this, website operators must directly patch once they become aware of a new remote code execution vulnerability.

In addition, I would recommend to take additional preventive measures, e.g. to implement a Web Application Firewall or a Host based Intrusion Detection/Prevention System to make the installation more resilient against new vulnerabilities. If the website is operated on Linux it makes sense to activate AppArmor [6].

Have a great week.

O’Donnell L. Two Critical RCE Bugs Patched in Drupal 7 and 8 [Internet]. Threatpost | The first stop for security news. 2018 [cited 2018 Oct 20]. Available from: https://threatpost.com/two-critical-rce-bugs-patched-in-drupal-7-and-8/138468/
Drupal ST. Drupal Core – Multiple Vulnerabilities – SA-CORE-2018-006 [Internet]. Drupal.org. 2018 [cited 2018 Oct 20]. Available from: https://www.drupal.org/sa-core-2018-006
3.Drupal ST. Mime Mail – Critical – Remote Code Execution – SA-CONTRIB-2018-068 [Internet]. Drupal.org. 2018 [cited 2018 Oct 20]. Available from: https://www.drupal.org/sa-contrib-2018-068
CVE Details. Drupal Drupal : CVE security vulnerabilities, versions and detailed reports [Internet]. CVE Details. The ultimate security vulnerability datasource. 2018 [cited 2018 Oct 21]. Available from: https://www.cvedetails.com/product/2387/Drupal-Drupal.html?vendor_id=1367
Drupal.org. Usage statistics for Drupal core | Drupal.org [Internet]. 2018 [cited 2018 Oct 21]. Available from: https://www.drupal.org/project/usage/drupal
theMiddle. AppArmor: Say Goodbye to Remote Command Execution. [Internet]. Secjuice.com. 2018 [cited 2018 Oct 21]. Available from: https://www.secjuice.com/apparmor-say-goodbye-to-remote-command-execution/

IBM Webinar: Force the Bad Guys to Use Zero Day Exploits with Continuous Endpoint Enforcement and Patching

22 October 2016

On Tuesday, I watched the IBM webinar ‘Force the Bad Guys to Use Zero Day Exploits with Continuous Endpoint Enforcement and Patching’.

On slide 3 one could read the really interesting statement ‘NSA: no zero days were used in any high profile breaches over last 24 months’.

Slide 3 – Force the Bad Guys to Use Zero Day Exploits — and Why That’s a Good Thing

Curtis Dukes, deputy national manager of security systems within the NSA, said that NSA has been involved in incident response or mitigation efforts for all ‘high profile incidents’ one has read about in the Washington Post or the New York times.

In all this incidents hacker used somewhat simple technology like spear phishing, water holing and USB-drive delivery to get onto the victim’s networks.

In the last 24 months, not one zero day has been used in these high profile intrusions.

That is a very interesting insight. Moreover, Curtis Dukes said that

The fundamental problem we faced in every one of those incidents was poor cyber hygiene.

The central idea of the webinar is to harden all systems by applying at least all existing patches to the known vulnerabilities, and in a timely manner. For most of the organizations this is a great challenge: Applying an endless stream of operating system and application patches to thousands of servers and endpoints is a never-ending nightmare. But essential to hinder an attacker, who managed to get on the network, in his lateral movement across the network.

If an attacker cannot exploit existing vulnerabilities, he is forced to install hacking tools from his C&C server. But this will increase the likelihood of detection because the attacker creates anomalies which can be detected e.g. by a current anti-malware solution or a well-tuned SIEM system.

It is important to recognize that cyber hygiene shall not be restricted to patching and password rules. Operating systems offer lots of powerful inbuilt tools, e.g. PowerShell, which can be used by an attacker to move laterally across the network. Such movements a much harder to detect, because they are very similar to standard user behavior. Pass-the-hash attacks are another example where patching is of limited value only.

It is very important to understand what threats a security solution mitigates. But it is of crucial importance to know the gaps and to have some ideas on how to deal with them effectively.

Have a good weekend.

Canadian hospital under attack

26 March 2016

Reports on cyber-attacks don’t come to an end. Cyber-criminals seem to focus in particular on hospitals this year. In the case of the Norfolk General Hospital attackers modified the hospital’s homepage to serve the Teslacrypt ransomware to clueless visitors. The ransomware is delivered by drive-by download when the page is opened – you won’t even need to click on something on the page.

However, this does not mean that spear-phishing with malicious attachments is no longer modern. Cyber-criminals use a range of attack methods, and outdated application middleware on a server, which is connected to the Internet, is a worthwhile destination.

On Tuesday I got two spear phishing emails directly in my inbox. A short hack on VirusTotal showed that this were two zero days.

Two hours later, now at home, I analyzed the attachments in more details. Both attachments contained the same ransomware, but in different document formats. The attachments were now detected by 6 of 56 anti-malware systems on VirusTotal, e.g. by TrendMicro as W2KM_DRIDEX.YYSSH or by Avira as W2000M/Dldr.Agent.19573. That’s a reasonable result for classic anti-malware systems, although it means, that the anti-malware systems left the users unprotected for about 4 hours.

The VBA project with the auto-open macro was password protected. But LibreOffice writer was able to display the macros; it simply overrides the obviously weak VBA project protection functions of Microsoft Office.

W2KM_DRIDEX.YYSSH Code Sample. Click to enlarge.

The auto-open macro creates a file dsfsdfsdf.vbe, submits the file to the C&C server, downloads an executable named Fuckyourself.ass and runs it. Fuckyourself.ass is detected as e.g. by Microsoft as Backdoor:Win32/Drixed, by ESET as Win32/Dridex.AA.

COMODO File Execution Warning.

A next-gen endpoint protection solution would have containerized or blocked at least the critical event of executing dsfsdfsdf.vbe. An infection with Dridex would have been prevented. And this without any delay for updating malware patterns.

Happy Easter!

Bypassing protection measures by direct upload of malicious content to OneDrive/Office 365

9 August 2015

I am happy about every email with malicious content or attachment, in particular if I find the mail in my inbox. Sound’s strange, but it’s important to analyze the technology of the attackers to develop proper protection strategies.

Last Wednesday I spent an hour with the analysis of an obviously malicious email attachment. Outlook blocked the access to the attachment without any error message. Therefore I logged in to my outlook.com account and opened the email:

Malicious Mail in Outlook.com

A click on Download as zip resulted in the following error message:

The file “Automatische Lastschrift konnte nicht vorgenommen werden 05.08.2015.zip” is infected with an unknown virus, so it isn’t safe to download.

Perfect! This explains the strange behavior of Outlook. But saving to OneDrive surprisingly works.

Malicious Mail Save to OneDrive

Some minutes later I uploaded the zip archive to VirusTotal and found, that the malware was already known with name Trojan:Win32/Bulta!rfn. For more details please see below.

When I extracted the nested zip-archive to my local hard disk the endpoint protection system correctly identified the program, blocked access and took the predefined action.

What happened? The attackers used a standard technology (malware in nested zip archives) to deliver their payload. The outlook client and outlook.com both blocked downloading the payload because they identified a suspicious attachment.

But all protection could be bypassed by uploading the file to OneDrive. When OneDrive or Office 365 is used as collaboration platform with suppliers and partners an attacker could easily use bypass to distribute malicious content across companies. In particular for zero day exploits this may become a serious problem.

For protection against the download of malicious content from Cloud Services we have to change our endpoint protection strategy. The anti-malware systems on the surf proxy will not recognize the malicious objects because the data stream is encrypted (https protocol used). Even if the surf proxy breaks SSL it is very likely that zero day exploits, and already known viruses, are not identified. The same holds for the endpoint protection systems on the end-users desktops.

But the first line of defense, the cloud provider, has the most important task. Bypassing protection by uploading malicious objects to the cloud storage is not acceptable. This strange behavior should be corrected as soon as possible. From the above we know that this is an easy task because the system already identified the attachment as malware.

Have a good week!

VirusTotal results: 2015-08-06 20:21:06 UTC

Detection rate: 23 / 55

AntiVirus	Result	Last Update
Avast	Win32:Malware-gen	20150806
Microsoft	Trojan:Win32/Bulta!rfn	20150806
Ikarus	Trojan.Win32.Crypt	20150806
Arcabit	Trojan.Mikey.D538C	20150806
DrWeb	Trojan.Inject1.62743	20150806
TrendMicro	TROJ_KR.2B7B2BF7	20150806
TrendMicro-HouseCall	TROJ_KR.2B7B2BF7	20150806
Avira	TR/Crypt.Xpack.248161	20150806
Rising	PE:Trojan.Win32.Generic.18EBC66C!418104940	20150731
Sophos	Mal/Generic-S	20150806
AVG	Generic_r.FOY	20150806
Panda	Generic Suspicious	20150806
Emsisoft	Gen:Variant.Mikey.21388 (B)	20150806
Ad-Aware	Gen:Variant.Mikey.21388	20150806
BitDefender	Gen:Variant.Mikey.21388	20150806
F-Secure	Gen:Variant.Mikey.21388	20150806
GData	Gen:Variant.Mikey.21388	20150806
MicroWorld-eScan	Gen:Variant.Mikey.21388	20150806
McAfee-GW-Edition	BehavesLike.Ransom.lc	20150806
Kaspersky	Backdoor.Win32.Androm.humu	20150806
Symantec	Backdoor.Matsnu	20150806
McAfee	Artemis!B65DB4920F67	20150806
ESET-NOD32	a variant of Win32/Kryptik.DSND	20150806
ALYac		20150806
AVware		20150806
AegisLab		20150806
Agnitum		20150806
AhnLab-V3		20150806
Alibaba		20150803
Antiy-AVL		20150806
Baidu-International		20150806
Bkav		20150806
ByteHero		20150806
CAT-QuickHeal		20150806
ClamAV		20150806
Comodo		20150806
Cyren		20150806
F-Prot		20150806
Fortinet		20150804
Jiangmin		20150804
K7AntiVirus		20150806
K7GW		20150806
Kingsoft		20150806
Malwarebytes		20150806
NANO-Antivirus		20150806
Qihoo-360		20150806
SUPERAntiSpyware		20150806
Tencent		20150806
TheHacker		20150805
VBA32		20150806
VIPRE		20150806
ViRobot		20150806
Zillya		20150806
Zoner		20150806
nProtect		20150806

Nomination for the “Most-Slanting-Phishing-Site-of-the-Year” award

10 July 2015

I am receiving about 20 phishing mails a week. Most attackers invest a lot of effort in their counterfeits but, sometimes they overshoot the mark. My July candidate for the Most-Slanting-Phishing-Site-of-the-Year award is:

Most-Slanting-Phishing-Site-of-the-Year award – July 2015 candidate

Earlier this week the Italian company Hacking Team was hacked. The attackers made more than 400GB of confidential company data available to the public. The leaked data included tools and exploits provided by the company to carry out attacks, among them a new Flash Player zero day affecting Flash Player up to version 18.0.0.194.

Two critical vulnerabilities in as many weeks, that’s really annoying. The problem with the latest Flash Player attacks is that the payload is hidden in Flash Player SWF files. Thus, basically every SWF file might carry a malicious payload…

… It’s definitely time to solve the Flash Player problems once and for all.

Have a good weekend.

Adobe releases next emergency Flash zero-day patch

27 June 2015

Adobe Flash Player is a real source of irritation. New vulnerabilities are continuously made public. In the last three month 64 vulnerabilities were published in the NIST NVD Database, of which 43 with highest severity 10.0.

The latest vulnerability CVE-2015-3113, that potentially allows an attacker to take control of an affected system, is a technically advanced piece of malware. For technical details see the FireEye blog post ‘Operation Clandestine Wolf – Adobe Flash Zero-Day in APT3 Phishing Campaign’.

As usual the attack is started through a phishing email. And, once the attackers got access to the victim’s network, they move laterally through the network in the search of valuable information.

With this we have the first and second line of defense in a prevention strategy: User awareness training to support users in recognizing such attacks, and system isolation to prevent the attackers from moving laterally through the network.

Perhaps it’s time to solve this problem once and for all by uninstalling Flash Player…

Have a good weekend.

A brief introduction to Trusteer Apex Advanced Malware Protection

18 October 2014

The Trusteer approach to malware protection could be ground-breaking in the defence of zero-day exploits and phishing attacks.

Trusteer analysed millions of applications exposed to the Internet and created lists of valid application states and operations in a database.

For example, saving a web page to OneNote is a legitimate operation when it’s run from a process created by the user. In this case the Windows Explorer is the so-called parent process. If this operation is performed by an internet explorer process that has no valid parent process, it is very likely that a malicious operation is executed.

A watchdog process is monitoring the applications exposed to the Internet. If an application executes a sensitive operation the watchdog process checks its database and approves the operations if it’s valid. Invalid operations are rejected.

Brilliant idea! A watchdog process that checks the state of an application. I would appreciate it to get this for my windows phone. The ‘Here Drive+’ app hangs sometimes, in particular in foreign cities when you need it the most. A watchdog process could check the state and restart the process in such cases. This would be very helpful.

For more details about Trusteer Apex see the Trusteer Apex Product Flyer.

Unfortunately there are some minor flaws.

Trusteer Apex monitors only applications exposed to the Internet like Browsers, Java applets, Flash player or Office applications. Although the technology could also be used for protection against traditional malware like computer viruses, the product does not support this.

This means that Trusteer Apex is only useful in addition to traditional security products like an antivirus product.

Remember that every additional product increases the attack surface of your computer or network. It is not only the continuous patching to mitigate known vulnerabilities. Trusteer Apex receives e.g. application state updates across the internet, which could be tampered by an attacker. Moreover, the Trusteer computer scientists get their raw data from millions of computers operating in untrusted networks. If an attacker tampers some raw data and masks malicious states as valid, the entire installed base could be tampered.

This is the first signs of paranoia. I’m doing definitely too much threat modelling at the moment. But remind the words of Sigmund Freud:

‘The paranoid is never entirely mistaken.’

Just think of the impact of an attack against the master pattern database of a well-known provider of anti-malware software…

Don’t Panic!!

Share this:

Share this:

Share this:

Share this:

Share this:

Share this:

Share this:

Share this:

Share this:

Share this: