LiteLLM Weak JWT Authentication via Email-Based User Lookup

LiteLLM contains a weak authentication vulnerability that allows an attacker holding a valid JWT from the configured identity provider to authenticate as any existing user by exploiting an email-based fallback lookup in the JWT authentication flow without verifying the email_verified claim. Attackers can present a token with an unverified email address matching a victim's account to inherit the victim's role, including proxy_admin privileges, and permanently overwrite the victim's stored identity binding to retain persistent unauthorized access to administrative endpoints exposing API keys and user management.

Source published

28 Sep 2026 19:26:01 UTC

Source modified

1 Oct 2026 15:21:59 UTC

Observed here

23 Oct 2026 15:48:27 UTC

Source terms

CVE Program Terms of Use

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: cve-program · CVE Program Terms of Use. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 4.0 · 7.6 CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N

CVSS 3.1 · 8.1 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N