---
title: "CVE-2026-42271: BerriAI LiteLLM Command Injection Vulnerability"
url: https://erroneo.us/security/cve/CVE-2026-42271/
description: "CVE-2026-42271 (BerriAI LiteLLM): Exploited in the wild (CISA KEV). LiteLLM is a proxy server (AI Gateway) to call LLM APIs in OpenAI (or native) format.…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-05-08
date_modified: 2026-10-21
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-42271"
kev: true
cvss: 8.7
epss: 0.9257
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-42271: BerriAI LiteLLM Command Injection Vulnerability

**Signal:** Exploited: patch now if you run it. CISA has confirmed exploitation in the wild. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- Yes, if you run BerriAI LiteLLM. CISA added this CVE to its Known Exploited Vulnerabilities catalog on 2026-06-08, which means there is reliable evidence of exploitation in the wild. US federal agencies must remediate by 2026-06-22 ; treat that as the outer limit, not the target.
- EPSS 92.6% , percentile 99.8: FIRST’s model estimates a 92.6% chance of exploitation activity in the next 30 days, higher than 99.8% of all scored CVEs (very high). EPSS is a probability, not a verdict.
- Needs an account (low (any account)). 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. From version 1.74.2 to before version 1.83.7, two endpoints used to preview an MCP server before saving it — POST /mcp-rest/test/connection and POST /mcp-rest/test/tools/list — accepted a full server configuration in the request body, including the command, args, and env fields used by the stdio transport. When called with a stdio configuration, the endpoints attempted to connect, which spawned the supplied command as a subprocess on the proxy host with the privileges of the proxy process. The endpoints were gated only by a valid proxy API key, with no role check. Any authenticated user — including holders of low-privilege internal-user keys — could therefore run arbitrary commands on the host. This issue has been patched in version 1.83.7.

## Affected products (CVE record)

- BerriAI litellm: >= 1.74.2, < 1.83.7

## Severity

- GitHub_M CVSS 4.0: 8.7 `CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:N/SA:N`
- redhat-SADP CVSS 3.1: 8.8 `CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`

## Exploitation

- CISA KEV: added 2026-06-08; federal due date 2026-06-22. Known ransomware use: Unknown.
- CISA required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
- CISA SSVC assessment: exploitation active , automatable no , technical impact total .
- FIRST EPSS (model of 2026-10-21): 92.57% probability of exploitation activity in the next 30 days; percentile 99.8.

## Sources

- [access.redhat.com](https://access.redhat.com/errata/RHSA-2026:28960)
- [access.redhat.com](https://access.redhat.com/errata/RHSA-2026:30056)
- [access.redhat.com](https://access.redhat.com/errata/RHSA-2026:27784)
- [Listed in CISA KEV notes (github.com)](https://github.com/BerriAI/litellm/security/advisories/GHSA-v4p8-mg3p-g94g)
- [Listed in CISA KEV notes (github.com)](https://github.com/BerriAI/litellm/releases/tag/v1.83.7-stable)
- [CVE.org record CVE-2026-42271](https://www.cve.org/CVERecord?id=CVE-2026-42271)
- [NVD entry CVE-2026-42271](https://nvd.nist.gov/vuln/detail/CVE-2026-42271)
- [CISA Known Exploited Vulnerabilities catalog entry](https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-42271)
- [access.redhat.com](https://access.redhat.com/security/cve/CVE-2026-42271)
- [RHBZ#2467924](https://bugzilla.redhat.com/show_bug.cgi?id=2467924)
- [security.access.redhat.com](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-42271.json)

---
Source page: https://erroneo.us/security/cve/CVE-2026-42271/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt