HighVulnerabilityLLM-specific

CVE-2026-31942: LibreChat IDOR in API keys endpoint lets users overwrite other users' keys

Source: NVD(opens in a new tab)
Identifier: CVE-2026-31942
Published: June 2, 2026
Record updated: October 9, 2026

Known exploitation: Not listed in the CISA Known Exploited Vulnerabilities catalog at the last check.
EPSS: 0.2%

Summary

CVE-2026-31942 affects LibreChat in versions up to and including 0.7.6. An Insecure Direct Object Reference flaw in the PUT /api/keys endpoint lets any authenticated user add a userId parameter to the request body, which overwrites another user's API keys (such as OpenAI, Anthropic or Azure). An attacker could route a victim's conversations through attacker-controlled keys or cause denial of service with invalid keys.

Mitigation

Patched in version 0.8.3-rc1.

Details

Scores and exploitation

CVSS score: 7.1(high)
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L
Attack vector: network
Attack complexity: low
Privileges required: low
User interaction: none
EPSS: 0.2%Estimated probability that this CVE is exploited in the next 30 days, from the FIRST Exploit Prediction Scoring System. Read on November 4, 2026.
Disclosure date: June 2, 2026

Weaknesses and techniques

Weakness (CWE): CWE-862
Attack pattern (CAPEC): CAPEC-122

Affected

Vendors: OpenAI,
Anthropic

Classification

Attack type: Other
Attack sophistication: Trivial
AI component targeted: API
Impact: Confidentiality,
Integrity,
Availability
Labels: security

How this record was produced

Summaries, mitigations and labels on this page are generated automatically from the source. The linked source is authoritative. The source gives this advisory a description and no title, so the title above is a headline generated from the source text.

Original source: https://nvd.nist.gov/vuln/detail/CVE-2026-31942

First tracked: June 2, 2026 at 08:09 PM ET, from NVD/CVE Database

Classifier: claude-haiku-5-5, prompt v4

Classifier confidence: 95% (self-assessed)

Summary

Mitigation

Related items