{"id":"CVE-2026-49468","aliases":["GHSA-4xpc-pv4p-pm3w","PYSEC-2026-388"],"title":"LiteLLM: Authentication Bypass via Host Header Injection","summary":"LiteLLM: Authentication Bypass via Host Header Injection","severity":"critical","cvss":9.8,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","vendor":"litellm","product":"litellm","ecosystem":"pip","affected":["litellm < 1.84.0"],"patched":["litellm 1.84.0"],"published":"2026-06-16","updated":"2026-09-10","sourceUpdated":"2026-09-10T03:50:48.301716737Z","source":"OSV","sourceUrl":"https://osv.dev/vulnerability/GHSA-4xpc-pv4p-pm3w","references":[{"url":"https://github.com/BerriAI/litellm/security/advisories/GHSA-4xpc-pv4p-pm3w"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-49468"},{"url":"https://access.redhat.com/security/cve/CVE-2026-49468"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2491520"},{"url":"https://github.com/BerriAI/litellm"},{"url":"https://github.com/BerriAI/litellm/releases/tag/v1.84.0"},{"url":"https://github.com/advisories/GHSA-4xpc-pv4p-pm3w"},{"url":"https://github.com/pypa/advisory-database/tree/main/vulns/litellm/PYSEC-2026-388.yaml"},{"url":"https://pypi.org/project/litellm"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-49468.json"}],"tags":["osv","pip","exploit-available","ghsa"],"epss":0.00817,"epssPercentile":0.55617,"exploits":{"github":1,"githubRepos":["https://github.com/BiiTts/CVE-2026-49468-LiteLLM-Auth-Bypass"],"checkedAt":"2026-09-23T07:14:09.605Z"},"exploitAvailable":true,"cwe":["CWE-290"],"ingestedAt":"2026-06-29T14:31:47.465Z","slug":"CVE-2026-49468","body":"## Overview\n\n### Impact\n\nA Host-header parsing flaw in the LiteLLM proxy could, under specific conditions, allow unauthenticated access to protected management routes.\n\nThe auth layer derived the effective route from `request.url.path` in `litellm/proxy/auth/auth_utils.py::get_request_route()`, which Starlette reconstructs from the `Host` header. A crafted `Host` could therefore make the auth gate evaluate a different route from the one FastAPI dispatched.\n\n**Most deployments are not affected.** The bypass is blocked by any upstream layer that validates or normalizes `Host`, such as:\n\n- a CDN or WAF, such as Cloudflare\n- a reverse proxy with `server_name` allowlists\n- a host-based load balancer\n\n**LiteLLM Cloud customers are not affected.**\n\n### Patches\n\nFixed in **`1.84.0`**. Upgrade to `1.84.0` or later. No configuration change is required.\n\n### Workarounds\n\nIf upgrading is not immediately possible, place the proxy behind an upstream component that validates or normalizes the `Host` header before forwarding (a CDN/WAF, a reverse proxy with explicit `server_name` allowlists, or a cloud load balancer with host-based routing rules), or otherwise restrict network access to the proxy listener.\n\n### References\n\n- Patched release: [`v1.84.0`](https://github.com/BerriAI/litellm/releases/tag/v1.84.0)\n\n**Discovery Credit**: Le The Thang (KCSC) and Kim Ngoc Chung (One Mount Group)\n\n## Affected packages\n\n- `litellm < 1.84.0`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `litellm 1.84.0`","depth":"abyssal","depthScore":66,"depthScoreParts":{"impact":53.9,"likelihood":0.2,"exploitation":12,"ransomware":0},"changes":[{"seq":201707,"id":"CVE-2026-49468","ts":1789399642374,"field":"cvss","old":null,"new":"9.8"},{"seq":200439,"id":"CVE-2026-49468","ts":1789397269635,"field":"cvss","old":"9.8","new":null},{"seq":198362,"id":"CVE-2026-49468","ts":1789391867127,"field":"cvss","old":null,"new":"9.8"},{"seq":196154,"id":"CVE-2026-49468","ts":1789383521931,"field":"cvss","old":"9.8","new":null},{"seq":195083,"id":"CVE-2026-49468","ts":1789380404433,"field":"cvss","old":null,"new":"9.8"},{"seq":193870,"id":"CVE-2026-49468","ts":1789378389253,"field":"cvss","old":"9.8","new":null},{"seq":192657,"id":"CVE-2026-49468","ts":1789376346879,"field":"cvss","old":null,"new":"9.8"},{"seq":191444,"id":"CVE-2026-49468","ts":1789373290056,"field":"cvss","old":"9.8","new":null},{"seq":190229,"id":"CVE-2026-49468","ts":1789369238467,"field":"cvss","old":null,"new":"9.8"},{"seq":189016,"id":"CVE-2026-49468","ts":1789368169880,"field":"cvss","old":"9.8","new":null},{"seq":187799,"id":"CVE-2026-49468","ts":1789365091915,"field":"cvss","old":null,"new":"9.8"},{"seq":186586,"id":"CVE-2026-49468","ts":1789363154644,"field":"cvss","old":"9.8","new":null},{"seq":185372,"id":"CVE-2026-49468","ts":1789361044735,"field":"cvss","old":null,"new":"9.8"},{"seq":184159,"id":"CVE-2026-49468","ts":1789358056036,"field":"cvss","old":"9.8","new":null},{"seq":182410,"id":"CVE-2026-49468","ts":1789354170433,"field":"cvss","old":null,"new":"9.8"},{"seq":181203,"id":"CVE-2026-49468","ts":1789353038154,"field":"cvss","old":"9.8","new":null},{"seq":179996,"id":"CVE-2026-49468","ts":1789350107001,"field":"cvss","old":null,"new":"9.8"},{"seq":178789,"id":"CVE-2026-49468","ts":1789347993073,"field":"cvss","old":"9.8","new":null},{"seq":177582,"id":"CVE-2026-49468","ts":1789346238900,"field":"cvss","old":null,"new":"9.8"},{"seq":176375,"id":"CVE-2026-49468","ts":1789342907390,"field":"cvss","old":"9.8","new":null},{"seq":175829,"id":"CVE-2026-49468","ts":1789338691614,"field":"cvss","old":null,"new":"9.8"},{"seq":175699,"id":"CVE-2026-49468","ts":1789338511512,"field":"cvss","old":"9.8","new":null},{"seq":174494,"id":"CVE-2026-49468","ts":1789334700191,"field":"cvss","old":null,"new":"9.8"},{"seq":173289,"id":"CVE-2026-49468","ts":1789333380833,"field":"cvss","old":"9.8","new":null},{"seq":172103,"id":"CVE-2026-49468","ts":1789330951326,"field":"cvss","old":null,"new":"9.8"},{"seq":170917,"id":"CVE-2026-49468","ts":1789328507142,"field":"cvss","old":"9.8","new":null},{"seq":169712,"id":"CVE-2026-49468","ts":1789326994297,"field":"cvss","old":null,"new":"9.8"},{"seq":168507,"id":"CVE-2026-49468","ts":1789323561378,"field":"cvss","old":"9.8","new":null},{"seq":167302,"id":"CVE-2026-49468","ts":1789319451852,"field":"cvss","old":null,"new":"9.8"},{"seq":166097,"id":"CVE-2026-49468","ts":1789318454426,"field":"cvss","old":"9.8","new":null},{"seq":164892,"id":"CVE-2026-49468","ts":1789315635420,"field":"cvss","old":null,"new":"9.8"},{"seq":163687,"id":"CVE-2026-49468","ts":1789313371250,"field":"cvss","old":"9.8","new":null},{"seq":162482,"id":"CVE-2026-49468","ts":1789311765484,"field":"cvss","old":null,"new":"9.8"},{"seq":161277,"id":"CVE-2026-49468","ts":1789308412236,"field":"cvss","old":"9.8","new":null},{"seq":160782,"id":"CVE-2026-49468","ts":1789304338884,"field":"cvss","old":null,"new":"9.8"},{"seq":160329,"id":"CVE-2026-49468","ts":1789303900565,"field":"cvss","old":"9.8","new":null},{"seq":159390,"id":"CVE-2026-49468","ts":1789300349465,"field":"cvss","old":null,"new":"9.8"},{"seq":158620,"id":"CVE-2026-49468","ts":1789299405074,"field":"cvss","old":"9.8","new":null},{"seq":157584,"id":"CVE-2026-49468","ts":1789296531455,"field":"cvss","old":null,"new":"9.8"},{"seq":156379,"id":"CVE-2026-49468","ts":1789294491193,"field":"cvss","old":"9.8","new":null},{"seq":155174,"id":"CVE-2026-49468","ts":1789292737988,"field":"cvss","old":null,"new":"9.8"},{"seq":153969,"id":"CVE-2026-49468","ts":1789289470107,"field":"cvss","old":"9.8","new":null},{"seq":152619,"id":"CVE-2026-49468","ts":1789281389934,"field":"cvss","old":null,"new":"9.8"},{"seq":152259,"id":"CVE-2026-49468","ts":1789280992756,"field":"cvss","old":"9.8","new":null},{"seq":151220,"id":"CVE-2026-49468","ts":1789277486062,"field":"cvss","old":null,"new":"9.8"},{"seq":150181,"id":"CVE-2026-49468","ts":1789275976609,"field":"cvss","old":"9.8","new":null},{"seq":149148,"id":"CVE-2026-49468","ts":1789273651064,"field":"cvss","old":null,"new":"9.8"},{"seq":148115,"id":"CVE-2026-49468","ts":1789271015781,"field":"cvss","old":"9.8","new":null},{"seq":146155,"id":"CVE-2026-49468","ts":1789269235436,"field":"cvss","old":null,"new":"9.8"},{"seq":145057,"id":"CVE-2026-49468","ts":1789266221815,"field":"cvss","old":"9.8","new":null}]}