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Vulnerability Intelligence

CVE-2026-42271

HighExploitedPublic exploit

LiteLLM: Authenticated command execution via MCP stdio test endpoints

Published Apr 25, 2026 · Updated Sep 10, 2026 · Also known as GHSA-v4p8-mg3p-g94g, PYSEC-2026-2599

Key Facts

Patch immediately
  • CVE-2026-42271 is a high-severity vulnerability (CVSS 8.7 v4) affecting Litellm, Openshift Ai (Redhat), airflow-3 (chainguard) and 4 more products.
  • It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Jun 8, 2026 and is known to be used in ransomware campaigns. Public exploit code is available.
  • EPSS estimates a 93% probability of exploitation in the next 30 days.
  • Fixed versions are available, including airflow-3 3.2.2-r7, airflow-3 3.3.1-r0, Litellm 1.83.10.0-r0.
  • Brandefense priority: patch immediately, because it is listed as exploited in the wild.

CVSS v4

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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

EPSS (30-day exploit likelihood)

93%

Higher than 99.8% of all scored CVEs

Exploited in the wild

Yes

4 catalog listings, used by ransomware

Public exploit code

Available

Proof-of-concept or weaponized module

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Description

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.

Known-Exploited Catalog Listings

CatalogAddedRemediation dueRansomware use
CISA KEVJun 8, 2026Jun 22, 2026Not reported
Industry KEV feedJun 8, 2026Jun 22, 2026Known
CIRCL KEVJun 8, 2026Jun 22, 2026Not reported
ENISA EUVDJun 8, 2026n/aNot reported

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.

Affected Products

13 affected entries in total
ProductAffected versionsFixed in
LitellmLitellm>= 1.74.2, >= >= 1.74.2, < 1.83.71.83.7
Openshift AiRedhat3.42.25.8
airflow-3chainguardSee advisory3.2.2-r7
litellm-1.83minimosSee advisory1.83.10-r0
rhoai/odh-llama-stack-core-rhel9:1781826406redhatSee advisoryn/a
2 more affected products in the full CVE brief

Patched Releases

airflow-3

3.2.2-r7, 3.3.1-r0

Litellm

1.83.10.0-r0, 1.83.7

litellm-1.83

1.83.10-r0

Openshift Ai

2.25.8, 3.3.4

Timeline

  1. Publicly disclosed

    Apr 25, 2026

  2. Added to CISA KEV

    Jun 8, 2026

  3. Added to Industry KEV feed

    Jun 8, 2026

  4. Added to CIRCL KEV

    Jun 8, 2026

  5. Added to ENISA EUVD

    Jun 8, 2026

  6. Last updated

    Sep 10, 2026

Weakness Type

  • CWE-77 Improper Neutralization of Special Elements used in a Command ('Command Injection')
  • CWE-78 Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

References

15 more references in the full CVE brief

FAQ

Common Questions.

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