CVE-2026-41487

Langfuse is an open source large language model engineering platform. From version 3.68.0 to before version 3.167.0, there is a role-based-access control flaw in the LLM connection update flow. An authenticated, low-privileged user of role “member” in a project could request the update of an existing LLM connection to an attacker-controlled baseUrl, causing Langfuse to reuse the stored provider secret and redirect the test request to an attacker-controlled endpoint. This could expose the plaintext provider LLM API key for that connection. The attack is only possible if a user is already part of a project and has “member” scoped access. This issue has been patched in version 3.167.0.

CVSS v3 5.4 MEDIUM

5.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/langfuse/langfuse/commit/7527bb0d84bc0a3dc24a4b16d22ed2e46e6dddff	Patch
https://github.com/langfuse/langfuse/commit/e12386f9d4368bbfff24a4ad7fd53641091605ff	Patch
https://github.com/langfuse/langfuse/pull/13027	Issue Tracking Patch
https://github.com/langfuse/langfuse/pull/13055	Issue Tracking Patch
https://github.com/langfuse/langfuse/releases/tag/v3.167.0	Release Notes
https://github.com/langfuse/langfuse/security/advisories/GHSA-2524-j966-gfgh	Mitigation Patch Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:langfuse:langfuse:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-05-08 15:16

Updated : 2026-06-17 10:46

NVD link : CVE-2026-41487

Mitre link : CVE-2026-41487

CVE.ORG link : CVE-2026-41487

JSON object : View

Products Affected

langfuse

langfuse

CWE

CWE-284

Improper Access Control

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