CVE-2019-17026: Zero-Day Vulnerability in Mozilla Firefox Exploited in Targeted Attacks
Mozilla releases patch to address Firefox flaw being used as part of targeted attacks.
Background
On January 8, Mozilla Foundation released a security advisory to address a critical zero-day flaw in Mozilla Firefox, which has been exploited in targeted attacks.
Analysis
CVE-2019-17026 is a type confusion vulnerability in IonMonkey, the JavaScript Just-In-Time (JIT) compiler for SpiderMonkey, Mozilla’s JavaScript engine. According to Mozilla’s advisory, the flaw exists in the JIT compiler due to “incorrect alias information for setting array elements,” specifically in StoreElementHole and FallibleStoreElement.
The vulnerability was reported to Mozilla by researchers at Qihoo 360 ATA. Mozilla’s advisory states they are “aware of targeted attacks in the wild abusing this flaw.” Based on this note in the advisory, it appears the vulnerability was exploited in the wild as a zero-day. Further information about the exploitation was not available at the time this blog post was published.
This advisory follows the release of Firefox 72 and Firefox Extended Support Release (ESR) 68.4 on January 7, which included the following security advisories:
- Firefox 72: Mozilla Foundation Security Advisory 2020-01
- Firefox ESR 68.4: Mozilla Foundation Security Advisory 2020-02
Last year, Mozilla patched CVE-2019-11707, another type confusion flaw that was used in conjunction with CVE-2019-11708, a sandbox escape vulnerability in targeted attacks.
Proof of concept
At this time, no proof of concept is available for this vulnerability.
Solution
To address CVE-2019-17026, Mozilla released Firefox 72.0.1 and Firefox ESR 68.4.1. Because this vulnerability has been exploited in targeted attacks, Firefox users are advised to upgrade as soon as possible.
Identifying affected systems
A list of Tenable plugins to identify this vulnerability will appear here as they’re released.
Get more information
Join Tenable's Security Response Team on the Tenable Community.
Learn more about Tenable, the first Cyber Exposure platform for holistic management of your modern attack surface.
Get a free 30-day trial of Tenable.io Vulnerability Management.
Related Articles
Cybersecurity Snapshot: CISA Pinpoints Vulnerabilities in Critical Infrastructure Orgs that Ransomware Groups Could Exploit
March 17, 2023Learn about CISA’s new program to help critical infrastructure organizations stamp out vulnerabilities associated with ransomware attacks. Plus, a U.S. government advisory with the latest on LockBit 3.0. Also, find out why the U.K.’s cyber agency is warning users about ChatGPT. And much more!
Microsoft’s March 2023 Patch Tuesday Addresses 76 CVEs (CVE-2023-23397)
March 14, 2023Microsoft’s March 2023 Patch Tuesday Addresses 76 CVEs (CVE-2023-23397) Microsoft addresses 76 CVEs including two zero-days exploited in the wild, one of which was publicly disclosed. 9Critica...
Cybersecurity Snapshot: Find MITRE ATT&CK Complex? Need Help Mapping to It? There’s an App for That!
March 10, 2023Learn about a new tool that streamlines MITRE ATT&CK mapping. Plus, known vulnerabilities remain a major cyber risk – just ask LastPass. Also, discover why SaaS data protection remains difficult. Plus, a look at the U.S. National Cybersecurity Strategy. And much more!
Tenable Cyber Watch: A Look at the U.S. National Cybersecurity Strategy, A Powerful AI Tech Gears Up for Prime Time, and more
March 20, 2023This week’s edition of the Tenable Cyber Watch unpacks the White House’s National Cybersecurity Strategy and explores how artificial intelligence will help cyber teams with complex attacks. Also covered: Why software vendors should prepare to submit letters of attestation to the GSA.
OpenAI’s ChatGPT and GPT-4 Used as Lure in Phishing Email, Twitter Scams to Promote Fake OpenAI Tokens
March 17, 2023Hoping to cash in on the massive interest around OpenAI’s GPT-4 – ChatGPT’s new multimodal model – scammers have launched phishing campaigns via email and Twitter designed to steal cryptocurrency. Check out how they’re carrying out the scams and how you can avoid becoming a victim.
Cybersecurity Snapshot: CISA Pinpoints Vulnerabilities in Critical Infrastructure Orgs that Ransomware Groups Could Exploit
March 17, 2023Learn about CISA’s new program to help critical infrastructure organizations stamp out vulnerabilities associated with ransomware attacks. Plus, a U.S. government advisory with the latest on LockBit 3.0. Also, find out why the U.K.’s cyber agency is warning users about ChatGPT. And much more!
- Vulnerability Management
