CVE-2019-11510 : Critical Pulse Connect Secure Vulnerability Used in Sodinokibi Ransomware Attacks
Recent rash of ransomware attacks are leveraging an eight-month-old flaw in a popular SSL VPN solution used by large organizations and governments around the world.
Contexte
On January 4, security researcher Kevin Beaumont (@GossiTheDog) observed two "notable incidents" in which a vulnerability in a Secure Socket Layer (SSL) Virtual Private Network (VPN) solution was used to breach two organizations and install targeted ransomware.
New by me: Pulse Secure VPN flaw being used to deliver targeted ransomware to large organisations https://t.co/h4rrzbPOWG
— Kevin Beaumont (@GossiTheDog) January 4, 2020
In his blog, Beaumont says this vulnerability was used to gain access to the vulnerable networks, followed by a similar pattern: obtaining domain administrator access, installing Virtual Network Computing (VNC) using PsExec for lateral movement, disabling endpoint security tools and installing the Sodinokibi ransomware, also known as Sodin or REvil.
Scott Gordon, Chief Marketing Officer for Pulse Secure, issued the following statement regarding Beaumont’s blog:
“Threat actors will take advantage of the vulnerability that was reported on Pulse Secure, Fortinet and Palo Alto VPN products -- and in this case, exploit unpatched VPN servers to propagate malware, REvil (Sodinokibi), by distributing and activating the Ransomware through interactive prompts of the VPN interface to the users attempting to access resources through unpatched, vulnerable Pulse VPN servers.”
Analyse
Pulse Secure Vulnerability
CVE-2019-11510 is a critical arbitrary file disclosure vulnerability in Pulse Connect Secure, the SSL VPN solution from Pulse Secure. Exploitation of the vulnerability is simple, which is why it received a 10.0 rating using the Common Vulnerability Scoring System (CVSS). The flaw could allow a remote, unauthenticated attacker to obtain usernames and plaintext passwords from vulnerable endpoints.
While Pulse Secure issued an out-of-cycle patch for the vulnerability in April 2019, it garnered more attention after a proof of concept (PoC) for the flaw was made public in August 2019. Shortly after the PoC was released, reports began to surface that attackers were probing for vulnerable endpoints and attempting to exploit the flaw.
At the time, Troy Mursch, Chief Research Officer at Bad Packets, identified over 14,500 Pulse Secure VPN endpoints that were vulnerable to this flaw. Mursch has been working to notify affected organizations to patch the flaw while also publishing weekly reports on Twitter of scan results for vulnerable endpoints. According to the most recent scan result from January 3, 2020, Mursch detected 3,825 endpoints that remain vulnerable, with over 1,300 of those endpoints residing in the United States.
Sodinokibi (REvil) Ransomware
Sodinokibi (or REvil) first appeared in April 2019 as part of attacks utilizing a zero-day exploit for an unauthenticated remote code execution vulnerability in Oracle WebLogic identified as CVE-2019-2725. Additional research in July 2019 found that Sodinokibi also exploits CVE-2018-8453, an elevation of privilege flaw in Win32k, which the researchers called “rare among ransomware.”
Sodinokibi has been linked to the creators of the GandCrab ransomware, which shuttered its operations in May 2019 after earning a reported $2 billion in ransom payments.
Big Game Hunting Ransomware
The use of the term “Big Game Hunting” references a Crowdstrike blog from 2018 regarding the electronic crime group dubbed INDRIK SPIDER pivoting from banking trojans to targeted ransomware attacks using the BitPaymer ransomware. The “big game” component refers to threat actors shifting to “targeted, low-volume, high return” activity.
In the case of Sodinokibi, it appears this tactic has been fruitful. Security researcher Rik Van Duijn identified at least seven cases of Sodinokibi ransomware infections in the first six days of 2020 demanding over $10 million based on analyzed malware samples, underscoring just how much potential value there is in these big game hunting ransomware attacks.
REvil is starting the year strong, asking for some serious cash. We are working on a blog describing just how bad it is, hoping to launch end of the month.
— rik van duijn (@rikvduijn) January 6, 2020
cc @GossiTheDog pic.twitter.com/0Katzxd7aW
While Sodinokibi has been linked to various vulnerabilities mentioned above, it is important to note that ransomware in general spreads through a variety of methods, including unpatched software vulnerabilities, malicious emails and exposed remote desktop systems.
Démonstration de faisabilité (PoC)
The first PoC published for CVE-2019-11510 was released on August 20 to Exploit Database by security researchers Alyssa Herrera and Justin Wagner. There are also multiple PoCs to identify and/or exploit CVE-2019-11510 published to GitHub repositories.
Solution
As previously noted, Pulse Secure released patches for CVE-2019-11510 back in April 2019. If your organization utilizes Pulse Connect Secure in your environment, it is paramount that you patch as soon as possible. Additionally, because Sodinokibi uses CVE-2018-8453, it is also extremely important to ensure the appropriate security updates from Microsoft’s October 2018 Patch Tuesday have been applied.
Identification des systèmes affectés
A list of Tenable plugins to identify this vulnerability can be found here, which includes a direct exploit check, identified as Plugin ID 127897.
Où trouver plus d'informations
- Kevin Beaumont's Blog on Big Game Ransomware Exploiting CVE-2019-11510
- Out-of-Cycle Advisory for Multiple Vulnerabilities in Pulse Connect Secure
- Troy Mursch's Blog on 14,500 Vulnerable Pulse Secure VPN Endpoints
- Cisco Talos' Blog on Sodinokibi Ransomware Exploiting CVE-2019-2725
- Kaspersky's Blog on Sodinokibi Ransomware Using CVE-2018-8453
Rejoignez l'équipe SRT de Tenable sur Tenable Community.
Apprenez-en plus sur Tenable, la première plateforme de Cyber Exposure qui vous permet de gérer votre surface d'attaque moderne de manière globale.
Profitez d'un essai gratuit de 30 jours de Tenable.io Vulnerability Management.
Articles connexes
Strengthening the Nessus Software Supply Chain with SLSA
April 16, 2024You know Tenable as a cybersecurity industry leader whose world-class exposure management products are trusted by our approximately 43,000 customers, including about 60% of the Fortune 500. But sometimes we like to give you a peek behind the curtain to share how we protect our own house against cyberattacks – and that’s what this blog is about. Today we’re sharing our experience adopting the supply-chain security framework SLSA, with the hopes that the lessons we learned will be helpful to you.
Cybersecurity Snapshot: CISA Says Midnight Blizzard Swiped U.S. Gov’t Emails During Microsoft Hack, Tells Fed Agencies To Take Immediate Action
April 12, 2024Check out CISA’s urgent call for federal agencies to protect themselves from Midnight Blizzard’s breach of Microsoft corporate emails. Plus, a new survey shows cybersecurity pros are guardedly optimistic about AI. Meanwhile, SANS pinpoints the four trends CISOs absolutely must focus on this year. And the NSA is sharing best practices for data security. And much more!
Cybersecurity Snapshot: U.S. Gov’t Unpacks AI Threat to Banks, as NCSC Urges OT Teams to Protect Cloud SCADA Systems
March 29, 2024Check out new guidance for banks on combating AI-boosted fraud. Plus, how to cut cyber risk when migrating SCADA systems to the cloud. Meanwhile, why CISA is fed up with SQLi flaws. And best practices to prevent and respond to DDoS attacks. And much more!
Tenable and Thales Collaborate to Provide Cyber Defense Simulations to Better Secure Operational Technology Environments
April 18, 2024The heart of the Welsh Valleys is home to the Thales Ebbw Vale campus, a world-class facility jointly funded by the Welsh government as part of its regeneration program for the region. At the core of the facility is the Cyber Range, a simulation and virtualization platform for training, testing, exercising and R&D. Tenable has joined the lineup of solutions used to run real world simulations in this controlled environment.
Oracle April 2024 Critical Patch Update Addresses 239 CVEs
April 17, 2024Oracle addresses 239 CVEs in its second quarterly update of 2024 with 441 patches, including 38 critical updates.
Strengthening the Nessus Software Supply Chain with SLSA
April 16, 2024You know Tenable as a cybersecurity industry leader whose world-class exposure management products are trusted by our approximately 43,000 customers, including about 60% of the Fortune 500. But sometimes we like to give you a peek behind the curtain to share how we protect our own house against cyberattacks – and that’s what this blog is about. Today we’re sharing our experience adopting the supply-chain security framework SLSA, with the hopes that the lessons we learned will be helpful to you.
- Vulnerability Management