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KEV catalog · CISA Known Exploited Vulnerabilities

CVE-2026-42271 8.8
BerriAI · LiteLLM · Added 2026-06-08 · Published 2026-05-08
3-Day Required KEV Active Exploitation

Details

VulnerabilityBerriAI LiteLLM Command Injection Vulnerability
VendorBerriAI
ProductLiteLLM
Date added2026-06-08
Due date2026-06-22
Required actionApply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
CWECWE-77 CWE-78
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Descriptions

KEV: BerriAI LiteLLM contains a command injection vulnerability that could allow any authenticated user, including holders of low-privilege internal-user keys, to run arbitrary commands on the host.

NVD: 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.

Compliance SSVC + BOD 26-04

Automatableno
Technical impacttotal
Exploitation statusactive
3-day qualifyingYes
Public timeline3 days + forensic
Non-public timeline14 days
Forensic (public)Required
Forensic (non-public)Not required

Research metadata

Last researched2026-06-16 22:03 UTC
Wall time120s
Searches6
Component defaultunknown

QC notes

info precondition_contradiction: Preconditions don't mention deployment applicability (component/product version)
warn component_extraction: Component 'LiteLLM MCP stdio transport preview endpoints (/mcp-rest/test/connection and /mcp-rest/test/tools/list)' matches or contains product name 'LiteLLM' — no specific component identified

Hunting hypothesis agent

Hunt for POST requests to LiteLLM MCP preview endpoints with crafted stdio transport configs injecting OS commands through non-standard executable paths.

Research details

ComponentLiteLLM MCP stdio transport preview endpoints (/mcp-rest/test/connection and /mcp-rest/test/tools/list)
PreconditionsAttacker must have network access to a vulnerable LiteLLM proxy server (v1.74.2 to before v1.83.7). The attacker sends POST requests to /mcp-rest/test/connection or /mcp-rest/test/tools/list with a crafted stdio transport configuration (command, args, env fields) in the request body. The server spawns the attacker-supplied command as a subprocess when attempting to connect to the specified MCP server. Authentication is required via a valid proxy API key (any role including low-privilege internal-user keys), but can be bypassed by chaining with CVE-2026-48710 (Starlette BadHost) for unauthenticated exploitation. agent
DeliveryPOST requests to /mcp-rest/test/connection or /mcp-rest/test/tools/list with crafted stdio transport configuration in JSON body
Public PoCno
Exploit notesCVSS attack complexity: LOW | HIGH severity (CVSS 8.8) | Can be chained with CVE-2026-48710 for unauthenticated RCE (CVSS 10.0) | EPSS probability 53.7% (99th percentile) | Active exploitation confirmed
SummaryCVE-2026-42271 is an authenticated (or unauthenticated via CVE-2026-48710 chain) command injection vulnerability in BerriAI LiteLLM proxy v1.74.2-v1.83.7. Two MCP preview endpoints (/mcp-rest/test/connection and /mcp-rest/test/tools/list) accept stdio transport configurations that spawn attacker-supplied commands as subprocesses on the host. Added to CISA KEV on 2026-06-08 with active exploitation confirmed. No public PoC identified. Vendor advisory (GHSA-v4p8-mg3p-g94g) and patch in v1.83.7 available.

Tia coverage

First reported2026-05-28
First exploit report2026-06-09
Exploit report → KEV1 days after the listing

When Tia's reporting first covered this CVE and whether a report claimed exploitation before the KEV listing. Lead-time deltas are measured from the exploitation report only — plain coverage is not exploitation intel. See the story links under Mentioned in for coverage detail.

Mentioned in

badhost-cve-2026-48710-starlette-host-header-injection-bypasseshackers-are-targeting-ai-servers-to-steal-api-keys-and-install-chackers-target-litellm-ragflow-and-kestra-ai-infrastructure-to-s

Record schema v1.0. Enrichment is research-grade, not a substitute for analyst review.

Source on GitHub