archive

Exploit

  1. How Memory Forensics Revealed Exploitation of Ivanti Connect Secure VPN Zero-Day Vulnerabilities

    In a recent series of blog posts related to two zero-day vulnerabilities in Ivanti Connect Secure VPN, Volexity shared details of active in-the-wild exploitation; provided an update on how exploitation had gone worldwide; and reported observations of how malware and modifications to the built-in Integrity Checker Tool were used to evade detection. A critical piece of Volexity’s initial investigation involved collecting and analyzing a memory sample. As noted in the first blog post of the three-part series (emphasis added): “…Volexity analyzed one of the collected memory samples and uncovered the exploit chain used by the attacker. Volexity discovered two different zero-day exploits which were being chained together to achieve unauthenticated remote code execution (RCE). Through forensic analysis of the memory sample, Volexity was able to recreate two proof-of-concept exploits that allowed full unauthenticated command execution on the ICS VPN appliance.” Collect & Analyze Memory ASAP Volexity regularly prioritizes memory forensics […]

  2. Ivanti Connect Secure VPN Exploitation: New Observations

    On January 15, 2024, Volexity detailed widespread exploitation of Ivanti Connect Secure VPN vulnerabilities CVE-2024-21887 and CVE-2023-46805. In that blog post, Volexity detailed broader scanning and exploitation by threat actors using still non-public exploits to compromise numerous devices. The following day, January 16, 2024, proof-of-concept code for the exploit was made public. Subsequently, Volexity has observed an increase in attacks from various threat actors against Ivanti Connect Secure VPN appliances beginning the same day. Additionally, Volexity has continued its investigation into activity conducted by UTA0178 and made a few notable discoveries. The first relates to the GIFTEDVISITOR webshell that Volexity scanned for, which led to the initial discovery of over 1,700 compromised Ivanti Connect Secure VPN devices. On January 16, 2024, Volexity conducted a new scan for this backdoor and found an additional 368 compromised Ivanti Connect Secure VPN appliances, bringing the total count of systems infected by GIFTEDVISITOR to […]

  3. Ivanti Connect Secure VPN Exploitation Goes Global

    Important: If your organization uses Ivanti Connect Secure VPN and you have not applied the mitigation, then please do that immediately! Organizations should immediately review the results of the built-in Integrity Check Tool for log entries indicating mismatched or new files. As of version 9.1R12, Ivanti started providing a built-in Integrity Checker Tool that can be run as a periodic or scheduled scan. Volexity has observed it successfully detecting the compromises described in this post across impacted organizations. Last week, Ivanti also released an updated version of the external Integrity Checker Tool that can be further used to check and verify systems. On January 10, 2024, Volexity publicly shared details of targeted attacks by UTA0178 exploiting two zero-day vulnerabilities (CVE-2024-21887 and CVE-2023-46805) in Ivanti Connect Secure (ICS) VPN appliances. On the same day, Ivanti published a mitigation that could be applied to ICS VPN appliances to prevent exploitation of these […]

  4. Active Exploitation of Two Zero-Day Vulnerabilities in Ivanti Connect Secure VPN

    Volexity has uncovered active in-the-wild exploitation of two vulnerabilities allowing unauthenticated remote code execution in Ivanti Connect Secure VPN devices. An official security advisory and knowledge base article have been released by Ivanti that includes mitigation that should be applied immediately. However, a mitigation does not remedy a past or ongoing compromise. Systems should simultaneously be thoroughly analyzed per details in this post to look for signs of a breach. During the second week of December 2023, Volexity detected suspicious lateral movement on the network of one of its Network Security Monitoring service customers. Upon closer inspection, Volexity found that an attacker was placing webshells on multiple internal and external-facing web servers. These detections kicked off an incident response investigation across multiple systems that Volexity ultimately tracked back to the organization’s Internet-facing Ivanti Connect Secure (ICS) VPN appliance (formerly known as Pulse Connect Secure, or simply Pulse Secure). A closer inspection […]

  5. EvilBamboo Targets Mobile Devices in Multi-year Campaign

    Volexity has identified several long-running and currently active campaigns undertaken by the threat actor Volexity tracks as EvilBamboo (formerly named Evil Eye) targeting Tibetan, Uyghur, and Taiwanese individuals and organizations. These targets represent three of the Five Poisonous Groups of Chinese Communist Party (CCP). Volexity has tracked the activities of EvilBamboo for more than five years and continues to observe new campaigns from this threat actor. In September 2019, Volexity described the deployment of a reconnaissance framework and custom Android malware targeting both the Uyghur and Tibetan communities. In April 2020, Volexity detailed attacks by this threat actor against iOS devices, using a Safari exploit to infect Uyghur users with custom iOS malware. Key highlights from Volexity’s recent investigations include the following: Android targeting: Development of three custom Android malware families, BADBAZAAR, BADSIGNAL, and BADSOLAR, to infect CCP adversaries is ongoing. Fake websites and social media profiles: The attacker has […]

  6. Mass Exploitation of (Un)authenticated Zimbra RCE: CVE-2022-27925

    [Note: Volexity has reported all findings in this post to Zimbra. Where an existing contact was known, Volexity has notified local CERTs of compromised Zimbra instances in their constituency. The newest versions of Zimbra are patched for both the RCE vulnerability and authentication bypass vulnerabilities described in this blog.] In July and early August 2022, Volexity worked on multiple incidents where the victim organization experienced serious breaches to their Zimbra Collaboration Suite (ZCS) email servers. Volexity’s investigations uncovered evidence indicating the likely cause of these breaches was exploitation of CVE-2022-27925, a remote-code-execution (RCE) vulnerability in ZCS. This initial CVE was patched by Zimbra in March 2022 in 8.8.15P31 and 9.0.0P24. Figure 1. Description of CVE-2022-27925 from the NIST website Initial research into the vulnerability did not uncover any public exploit code, but since a patch had been available for several months, it was reasonable that exploit code could have been […]

  7. DriftingCloud: Zero-Day Sophos Firewall Exploitation and an Insidious Breach

    Volexity frequently works with individuals and organizations heavily targeted by sophisticated, motivated, and well-equipped threat actors from around the world. Some of these individuals or organizations are attacked infrequently or on an irregular basis, while others see a barrage of attacks nearly every week. Regardless of the attack frequency, Volexity keeps its guard up, looking for new and old threats however they manifest themselves. Earlier this year, Volexity detected a sophisticated attack against a customer that is heavily targeted by multiple Chinese advanced persistent threat (APT) groups. This particular attack leveraged a zero-day exploit to compromise the customer’s firewall. Volexity observed the attacker implement an interesting webshell backdoor, create a secondary form of persistence, and ultimately launch attacks against the customer’s staff. These attacks aimed to further breach cloud-hosted web servers hosting the organization’s public-facing websites. This type of attack is rare and difficult to detect. This blog post serves […]

  8. Zero-Day Exploitation of Atlassian Confluence

    UPDATE: On June 3, 2022, Atlassian updated its security advisory with new information regarding a fix for Confluence Server and Data Center to address CVE-2022-26134. Users are encouraged to update immediately to mitigate their risk. Additional observations after publication of this blog post have been shared here, with guidance on how to verify if you have been impacted by unauthorized access.  Over the Memorial Day weekend in the United States, Volexity conducted an incident response investigation involving two Internet-facing web servers belonging to one of its customers that were running Atlassian Confluence Server software. The investigation began after suspicious activity was detected on the hosts, which included JSP webshells being written to disk. Volexity immediately used Volexity Surge Collect Pro to collect system memory and key files from the Confluence Server systems for analysis. After a thorough review of the collected data, Volexity was able to determine the server compromise stemmed from […]

  9. Operation Exchange Marauder: Active Exploitation of Multiple Zero-Day Microsoft Exchange Vulnerabilities

    [UPDATE] March 8, 2021 – Since original publication of this blog, Volexity has now observed that cyber espionage operations using the SSRF vulnerability CVE-2021-26855 started occurring on January 3, 2021, three days earlier than initially posted. Volexity is seeing active in-the-wild exploitation of multiple Microsoft Exchange vulnerabilities used to steal e-mail and compromise networks. These attacks appear to have started as early as January 6, 2021. In January 2021, through its Network Security Monitoring service, Volexity detected anomalous activity from two of its customers’ Microsoft Exchange servers. Volexity identified a large amount of data being sent to IP addresses it believed were not tied to legitimate users. A closer inspection of the IIS logs from the Exchange servers revealed rather alarming results. The logs showed inbound POST requests to valid files associated with images, JavaScript, cascading style sheets, and fonts used by Outlook Web Access (OWA). It was initially suspected the […]

  10. Microsoft Exchange Control Panel (ECP) Vulnerability CVE-2020-0688 Exploited

    On February 11, 2020, as part of Patch Tuesday, Microsoft released cumulative updates and a service pack that addressed a remote code execution vulnerability found in Microsoft Exchange 2010, 2013, 2016, and 2019. The vulnerability was discovered by an anonymous security researcher and reported to Microsoft by way of Trend Micro’s Zero Day Initiative. Two weeks after the security updates were released, the Zero Day Initiative published a blog post providing more details on the vulnerability. The post made it clear that an attacker could exploit a vulnerable Exchange server if the following three criteria were met: The Exchange Server had not been patched since February 11, 2020. The Exchange Control Panel (ECP) interface was accessible to the attacker. The attacker has a working credential that allows them to access the Exchange Control Panel in order to collect the ViewStateKey from the authenticated session cookie as well as the __VIEWSTATEGENERATOR […]