Critical LiteLLM Host Header Flaw Enables Authentication Bypass
A critical vulnerability in LiteLLM tracked as CVE-2026-49468 allows attackers to bypass authentication through Host header injection and reach protected management endpoints. The flaw affects LiteLLM versions earlier than 1.84.0 and stems from a mismatch in how the authentication layer evaluates routes versus how FastAPI ultimately dispatches them, creating a path for unauthenticated access under specific conditions. The issue is classified as CWE-290 and has been rated CVSS 9.5, with researchers describing it as network-exploitable with low attack complexity and no user interaction required.
The vulnerability was responsibly disclosed by Le The Thang of KCSC and Kim Ngoc Chung of One Mount Group, and LiteLLM maintainers have released a fix in version 1.84.0 with no configuration changes required. There is no confirmed evidence of active exploitation, and LiteLLM Cloud customers are reportedly not affected. Self-hosted deployments may also be shielded if upstream infrastructure such as Cloudflare, WAFs, reverse proxies with strict allowlists, or host-validating load balancers normalize or reject malformed Host headers before requests reach the application.
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How this story unfolded
3 events from the most recent confirmed update back to the earliest known activity.
CVE-2026-49468 publicly disclosed for LiteLLM
The critical vulnerability CVE-2026-49468 was publicly disclosed as affecting LiteLLM versions before 1.84.0, with potential unauthenticated access to protected management endpoints under specific deployment conditions. Reports noted no confirmed exploitation at the time of disclosure.
LiteLLM fixes CVE-2026-49468 in version 1.84.0
LiteLLM patched the Host header injection authentication bypass vulnerability in version 1.84.0. The fix does not require configuration changes, and LiteLLM Cloud customers were reported as unaffected.
Researchers report LiteLLM auth bypass vulnerability
Le The Thang of KCSC and Kim Ngoc Chung of One Mount Group responsibly reported CVE-2026-49468, an authentication bypass flaw in LiteLLM caused by Host header injection and route handling discrepancies.
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LiteLLM Flaws Enable Privilege Escalation and OIDC Authentication Bypass
LiteLLM fixed two high-severity vulnerabilities in version `1.83.0` that could allow attackers to gain elevated access in AI gateway deployments. **CVE-2026-35029** stems from missing admin authorization on the `/config/update` endpoint, allowing an authenticated low-privilege user to change proxy settings and environment variables. The flaw could be abused to register attacker-controlled Python handlers for remote code execution, read arbitrary server files, and overwrite UI credentials to seize privileged accounts, creating broad confidentiality, integrity, and availability risk. The same release also addressed **CVE-2026-35030**, an authentication bypass affecting LiteLLM deployments that enabled JWT-based authentication. In vulnerable versions, the platform used the first 20 characters of a token as the OIDC userinfo cache key, allowing a crafted token with a matching prefix to collide with a legitimate cached session and inherit that user’s identity and permissions. The issue is not enabled by default, limiting exposure to specific configurations, but together the flaws highlight significant access-control weaknesses in LiteLLM versions prior to `1.83.0`.
Apr 29, 2026
Active Exploitation of LiteLLM Flaw Enables Unauthenticated RCE via Starlette Chain
CISA added **CVE-2026-42271** to its Known Exploited Vulnerabilities catalog after evidence emerged that attackers are exploiting a command injection flaw in BerriAI **LiteLLM**. The bug affects MCP server test endpoints in self-hosted LiteLLM deployments, where crafted `stdio` parameters can trigger arbitrary command execution on the proxy host. On its own, the flaw requires a valid proxy API key, but researchers reported it is being chained with **CVE-2026-48710** in **Starlette**—a Host header validation bypass known as **BadHost**—to bypass authentication and achieve unauthenticated remote code execution. The exposed attack path affects LiteLLM versions **1.74.2 through 1.83.6** when deployed with **Starlette 1.0.0 or earlier**, and researchers rated the combined chain as effectively **critical** with a CVSS score of **10.0**. Successful compromise can let attackers run OS commands, steal model provider credentials, API keys, secrets, and environment variables, and pivot into connected AI infrastructure. BerriAI patched the issue in **LiteLLM 1.83.7** by restricting the vulnerable test endpoints to the `PROXY_ADMIN` role, while defenders are being urged to upgrade LiteLLM and Starlette, limit network access to the affected endpoints, rotate stored credentials, and review logs for suspicious Host header and subprocess activity.
Jun 11, 2026
Critical LiteLLM SQL Injection Exploited to Target Stored API Keys and Credentials
Attackers began exploiting **CVE-2026-42208** in LiteLLM shortly after public disclosure, using a pre-authentication SQL injection flaw in the product’s `Authorization: Bearer` verification path to query the backend PostgreSQL database without logging in. The vulnerability, also tracked as `GHSA-r75f-5x8p-qvmc`, affects LiteLLM versions **1.81.16 through 1.83.6** and was fixed in **v1.83.7** after the project replaced vulnerable string interpolation with a parameterized query. Sysdig said the first observed exploitation attempt arrived **36 hours and seven minutes** after the advisory was indexed, with activity focused on enumerating high-value tables holding virtual API keys, provider credentials, verification tokens, and environment-based configuration. Researchers described the intrusion attempts as targeted rather than opportunistic, citing knowledge of Prisma-generated PostgreSQL table names and `UNION`-based column discovery; while no confirmed follow-on abuse was observed, defenders are being urged to patch exposed instances immediately, rotate all stored secrets, and review logs and billing accounts for signs of compromise.
May 11, 2026