CVE-2026-42203
HighCVSS 8.8Exploitation Probability (EPSS)
Low risk30th percentile - higher than 30% of all known CVEs
Summary
LiteLLM versions 1.80.5 through 1.83.7 have a vulnerability in the POST /prompts/test endpoint that accepts user-supplied prompt templates and renders them without sandboxing. A crafted template can execute arbitrary code within the LiteLLM Proxy process.
Risk Assessment
An authenticated user with a valid proxy API key can exploit this vulnerability to run arbitrary code on the host, potentially exposing sensitive data such as provider API keys or database credentials.
Recommendation
Immediately upgrade LiteLLM to version 1.83.7 or later, which includes a fix for this vulnerability.
Other vulnerabilities in LiteLLM
See all- CVE-2026-30623Critical
LiteLLM 1.18.10 contains a remote code execution vulnerability in its MCP server creation functionality. The application allows users to add MCP servers via a JSON configuration specifying arbitrary command and args values, which are executed on the host without validation. This enables attackers to run arbitrary operating system commands.
- CVE-2026-49468Critical
LiteLLM proxy before version 1.84.0 has a Host-header parsing flaw that, under specific conditions, allows unauthenticated access to protected management routes. The issue arises from a mismatch between the route evaluated by the auth layer and the route actually dispatched by FastAPI.
- CVE-2026-42271HighActively exploited
LiteLLM versions 1.74.2 through 1.83.6 have a vulnerability in the POST /mcp-rest/test/connection and POST /mcp-rest/test/tools/list endpoints, which accept a full MCP server configuration including commands to execute. An authenticated user with any API key can run arbitrary commands on the proxy host.
- CVE-2026-42208CriticalActively exploited
In LiteLLM versions from 1.81.16 to before 1.83.7, a database query used during proxy API key checks is vulnerable to SQL injection due to mixing caller-supplied key value into the query text. An unauthenticated attacker can send a crafted Authorization header to any LLM API route, leading to reading and potentially modifying data in the proxy's database.
- CVE-2026-40217High
A vulnerability in LiteLLM through 2026-04-08 allows remote attackers to execute arbitrary code via bytecode rewriting at the /guardrails/test_custom_code URI.
- CVE-2026-35030Critical
In LiteLLM prior to 1.83.0, when JWT authentication is enabled (enable_jwt_auth: true), the OIDC userinfo cache uses the first 20 characters of the token as the cache key. JWT tokens produced by the same signing algorithm have identical first 20 characters, allowing an unauthenticated attacker to craft a token matching the cache and inherit a legitimate user's identity and permissions.
- CVE-2026-35029High
LiteLLM before version 1.83.0 has a vulnerability where the /config/update endpoint does not enforce admin role authorization. An authenticated user can modify proxy configuration, environment variables, and register custom pass-through endpoint handlers, leading to remote code execution, arbitrary file reading, and takeover of privileged accounts.
- CVE-2026-37004Low risk· EPSS 16%
BerriAI litellm <=1.82.4 is vulnerable to Server-Side Template Injection (SSTI), allowing unauthenticated remote attackers to execute arbitrary OS commands via a crafted dotprompt_content parameter in the /prompts/test endpoint due to use of an unsandboxed jinja2.Environment.
- CVE-2026-59822High
LiteLLM before version 1.84.0 has a vulnerability in the MCP Streamable HTTP endpoint that allows an unauthenticated attacker to bypass LiteLLM key validation using a crafted Authorization header. The attacker can exploit the OAuth2 passthrough fallback path to replace failed key validation with an empty UserAPIKeyAuth() object, allowing requests to reach MCP tooling without a valid key.
- CVE-2026-59821High
LiteLLM prior to version 1.82.0-stable did not apply proper sandboxing and validation for Custom Code Guardrails during creation and update, allowing a privileged user to execute arbitrary Python code in the proxy environment and potentially expose process secrets.
Original NVD description (English source)
LiteLLM is a proxy server (AI Gateway) to call LLM APIs in OpenAI (or native) format. From version 1.80.5 to before version 1.83.7, the POST /prompts/test endpoint accepted user-supplied prompt templates and rendered them without sandboxing. A crafted template could run arbitrary code inside the LiteLLM Proxy process. The endpoint only checks that the caller presents a valid proxy API key, so any authenticated user could reach it. Depending on how the proxy is deployed, this could expose secrets in the process environment (such as provider API keys or database credentials) and allow commands to be run on the host. This issue has been patched in version 1.83.7.