Auth bypass in Berriai Litellm

CVE-2026-35029

LiteLLM is a proxy server (AI Gateway) to call LLM APIs in OpenAI (or native) format. Prior to 1.83.0, the /config/update endpoint does not enforce admin role authorization. A user who is already authenticated into the platform can then use this endpoint to modify proxy configuration and environment variables, register custom pass-through endpoint handlers pointing to attacker-controlled Python code, achieving remote code execution, read arbitrary server files by setting UI_LOGO_PATH and fetching via /get_image, and take over other privileged accounts by overwriting UI_USERNAME and UI_PASSWORD environment variables. Fixed in v1.83.0.

Vulnerability class: Broken Access Control

Published · last modified .

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.040 (90.1th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 90th percentile — 90.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-35029: fell from 0.264 to 0.040.

EPSS over last 30 days · oldest: 0.264 · newest: 0.040 · change: -0.224

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2026-35029?
CVE-2026-35029 is a high-severity vulnerability in Berriai Litellm, classified under Incorrect Authorization. CVSS score: 8.8/10. Published 2026-04-06.
How severe is CVE-2026-35029?
High severity. CVSS v3 base score is 8.8 out of 10.
Is CVE-2026-35029 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.