CVE-2026-42271Known exploitationPublic exploitNetwork attack vector

Authenticated command execution via MCP stdio test endpoints

Published May 8, 2026 · Updated May 8, 2026

Command injection in BerriAI LiteLLM 1.74.2 through 1.83.6 allows remote authenticated users to execute host commands via MCP test endpoints. The /mcp-rest/test/connection and /mcp-rest/test/tools/list handlers pass request-controlled stdio command, args, and env values to subprocess creation. Any valid proxy API key, including a low-privilege internal-user key, reaches the handlers, and spawned commands inherit the proxy process's host privileges.

CVSS severity8.7
High
EPSS probability91.44%
Next 30 days · Nov 1, 2026
Known exploitationReported
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Command injection in BerriAI LiteLLM 1.74.2 through 1.83.6 allows remote authenticated users to execute host commands via MCP test endpoints. The /mcp-rest/test/connection and /mcp-rest/test/tools/list handlers pass request-controlled stdio command, args, and env values to subprocess creation. Any valid proxy API key, including a low-privilege internal-user key, reaches the handlers, and spawned commands inherit the proxy process's host privileges.

The record

CVE
CVE-2026-42271
Published
May 8, 2026
Updated
May 8, 2026
Vendor
Berri AI
Product
LiteLLM
Classifications
CWE-78, CWE-77, T1059
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. May 8, 2026CVE publishedPublication date reported by the CVE source.
  2. May 8, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=>= 1.74.2, < 1.83.7

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Berri AI · LiteLLMversion=>= 1.74.2, < 1.83.7

Published CVSS scores

8.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
8.7GitHub, Inc.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
8.8Red HatCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Activity data is delayed. The latest report is Sep 28, 2026.

Daily unique IPsShadowserver observations through Sep 28, 2026. Gaps indicate unavailable data.
Sep 22, 2026Sep 28, 2026
View daily counts
Reporting dayUnique IPs
Sep 22, 202650
Sep 23, 202645
Sep 24, 202645
Sep 25, 202647
Sep 26, 202643
Sep 27, 202646
Sep 28, 202644
Latest reporting daySep 28, 2026
Latest daily unique IPs44
Prior 30-day average58.1
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationReported
Public exploitPublished

Weakness, pattern, technique

CWE-78Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
CWE-77Improper Neutralization of Special Elements used in a Command ('Command Injection')
T1059Command and Scripting Interpreter

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Reported exploitation

Technologies

Your stack

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Your stack

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