CVE-2026-84939(apache / freemarker)

LOWCVSS 9.1 · CRITICAL

Signal is active with 1 mentions in latest observed window

Immediate actions

  • Track advisory updates for patch or workaround availability

Recommended action window: Monitor and triage in normal cycle

NVD 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.

0.0/ 10 priority

Sources & remediation

Weakness type (CWE)
CWE-23

Priority

LOW

Exploitation

NONE

PoC

NONE

Patch

NONE

Momentum

NONE

Are you affected?

If you run products in this scope, you should treat this CVE as relevant to your environment.

  • freemarker

Threat summary

  • 1 mentions across 1 observed day

What's happening

  • 1 total mentions across 1 day

Affected systems

Vendors
Products
freemarker

Deep dive

Activity timeline1 mentions / 1d
00111Mentions · 2026-10-01: 110-01
Full discourse1 post
  • Cloud-IAM@cloud_iam_com

    CVE-2026-84939 - 9.1 (Apache FreeMarker) By default, Keycloak does not pass a user-controlled locale or template name to FreeMarker template loading, but a custom extension could. In that case, an attacker could access other files reachable by FreeMarker's template loader.

    1002017
    215 followersView on X
CPE platform detail1 entries

1 of 1 entries

PartVendorProductVersionTarget SWTarget HW
Appapachefreemarker---

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