CVE-2026-84939
Last modified
CVE-2026-84939 is a critical-severity vulnerability rated 9.1/10 on the CVSS scale. Path traversal vulnerability in Apache FreeMarker template loading mechanism, if the attacker can specify an arbitrary malformed locale identifier to FreeMarker, and the localized lookup configuration setting is enabled (it's by default enabled). This issue affects Apache FreeMarker from 2.2.0 through 2.3.34. Users are recommended to upgrade to version 2.3.35. Disabling localized lookup in previous versions also mitigates this. Note that even in versions affected by this vulnerability, the files that can be loaded remain restricted by the TemplateLoader that FreeMarker is configured to use. EPSS estimates a 0.21% chance of exploitation in the next 30 days.
Description
Path traversal vulnerability in Apache FreeMarker template loading mechanism, if the attacker can specify an arbitrary malformed locale identifier to FreeMarker, and the localized lookup configuration setting is enabled (it's by default enabled). This issue affects Apache FreeMarker from 2.2.0 through 2.3.34. Users are recommended to upgrade to version 2.3.35. Disabling localized lookup in previous versions also mitigates this. Note that even in versions affected by this vulnerability, the files that can be loaded remain restricted by the TemplateLoader that FreeMarker is configured to use. In particular, FileTemplateLoader prevents attempts to traverse outside the baseDir specified in its constructor. Other TemplateLoader implementations may allow access outside their designated base directory, but they are still constrained by the underlying storage mechanism—for example, a loader wrapping a Java class loader can only access resources that the class loader can load, while one wrapping a web application context can only access resources available through that context.
Metrics
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Apache | Freemarker | >= 2.2, < 2.3.35 |
References
- https://lists.apache.org/thread/hrd7o2ylwkkswdyhyzllgqt0f80kyd5yMailing List, Vendor Advisory
- https://www.openwall.com/lists/oss-security/2026/09/08/2Mailing List, Third Party Advisory
Timeline
- Published
- Last Modified
- Status
- Analyzed
Frequently Asked Questions
What is CVE-2026-84939?
How severe is CVE-2026-84939?
How do I fix CVE-2026-84939?
How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
- Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
- AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.
Related CVEs from 2026
- CVE-2026-84931The Joli Table Of Contents WordPress plugin before 3.0.3 doe…6.8
- CVE-2026-84933undici's cache interceptor does not handle the Set-Cookie re…6.5
- CVE-2026-84934The JCH Optimize WordPress plugin before 6.0.1 does not perf…8
- CVE-2026-84935The HT Menu WordPress plugin before 1.2.7 does not perform …8
- CVE-2026-84936The EmbedPress WordPress plugin before 4.6.4 does not have …5.3
- CVE-2026-84937The Video Player for YouTube WordPress plugin before 2.1.0 …6.8
- CVE-2026-8494The Permalink Manager Lite plugin for WordPress is vulnerabl…6.4
- CVE-2026-84941An information disclosure vulnerability in the SAML Single S…6.9
- CVE-2026-84942Improper input validation in the Vega expression function im…8.7
- CVE-2026-84947undici's dump interceptor reads and discards a response body…3.7
- CVE-2026-8495Missing Authorization vulnerability in Drupal Date iCal allo…9.8
- CVE-2026-8496A cross-site scripting (XSS) vulnerability exists in Alinto …6.1
Are you affected by CVE-2026-84939?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST
