---
title: "CVE-2026-59821: LiteLLM: Custom Code Guardrails production endpoints bypass code safety checks"
url: https://erroneo.us/security/cve/CVE-2026-59821/
description: "CVE-2026-59821 (BerriAI litellm): LiteLLM is a proxy server (AI Gateway) to call LLM APIs in OpenAI (or native) format. Prior to 1.82.0-stable, LiteLLM's…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-07-08
date_modified: 2026-10-21
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-59821"
kev: false
cvss: 2.1
epss: 0.00904
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-59821: LiteLLM: Custom Code Guardrails production endpoints bypass code safety checks

**Signal:** Normal patch cycle. No exploitation signal; fix it in your next routine update if you are affected. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
- EPSS 0.9% , percentile 59: FIRST’s model estimates a 0.9% chance of exploitation activity in the next 30 days, higher than 59% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
- Needs an account (high (admin)). Exposure depends on who can log in.
- Editorial verdict: Patch this week. LiteLLM Proxy: Three Exploited Flaws in CISA KEV — If you run a self-hosted LiteLLM Proxy older than 1.84.0, upgrade now and treat the provider keys it holds as possibly exposed; SDK-only users are not affected.

## What it is

LiteLLM is a proxy server (AI Gateway) to call LLM APIs in OpenAI (or native) format. Prior to 1.82.0-stable, LiteLLM's Custom Code Guardrails production create and update paths did not apply the same sandboxing and validation used by the test endpoint, allowing a privileged user with access to create or update guardrails to submit custom Python code that executed in the LiteLLM proxy environment and could expose secrets available to the process. This issue is fixed in version 1.82.0-stable.

## Affected products (CVE record)

- BerriAI litellm: < 1.82.0-stable

## Severity

- GitHub_M CVSS 4.0: 2.1 `CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation none , automatable no , technical impact partial .
- FIRST EPSS (model of 2026-10-21): 0.90% probability of exploitation activity in the next 30 days; percentile 59.

## Sources

- [CVE.org record CVE-2026-59821](https://www.cve.org/CVERecord?id=CVE-2026-59821)
- [NVD entry CVE-2026-59821](https://nvd.nist.gov/vuln/detail/CVE-2026-59821)
- [github.com](https://github.com/BerriAI/litellm/security/advisories/GHSA-72m8-9m7m-h278)
- [github.com](https://github.com/BerriAI/litellm/commit/e50b4486d0f7aa0497185a1ebcdd2c91f1769eba)
- [github.com](https://github.com/BerriAI/litellm/releases/tag/v1.82.0-stable)

---
Source page: https://erroneo.us/security/cve/CVE-2026-59821/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt