CVE-2026-84939

CRITICAL CVSS 3.1: 9.1 EPSS 0.85%
Updated Sep 11, 2026
Apache
Parameter Value
CVSS 9.1 (CRITICAL)
Affected Versions 2.2 — 2.3.35
Fixed In 2.3.35
Type CWE-23 (Relative Path Traversal)
Vendor Apache
Public PoC No

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.

Attack Parameters

Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed

Impact Assessment

Confidentiality
High
Complete data leak
Integrity
High
Complete data modification
Availability
None
No disruption

CVSS Vector v3.1

Vulnerable Products 1

Configuration From (including) Up to (excluding)
Apache Freemarker
cpe:2.3:a:apache:freemarker:*:*:*:*:*:*:*:*
2.2 2.3.35