{"id":"CVE-2026-59822","published":"2026-07-08T20:16:57Z","modified":"2026-10-25T17:10:00Z","title":"BerriAI LiteLLM Improper Authentication Vulnerability","vendor":"BerriAI","product":"LiteLLM","tier":"core","eol":null,"description":{"text":"LiteLLM is a proxy server (AI Gateway) to call LLM APIs in OpenAI (or native) format. Prior to 1.84.0, LiteLLM's MCP Streamable HTTP endpoint allowed an unauthenticated attacker to use a fabricated Authorization header to trigger an OAuth2 passthrough fallback path that replaced failed LiteLLM key validation with an empty UserAPIKeyAuth() object, allowing requests to reach MCP tooling without a valid LiteLLM key. This issue is fixed in version 1.84.0.","provenance":"source","from":"NVD"},"summary":{"text":"The improper authentication flaw in BerriAI's LiteLLM proxy server lives in its MCP Streamable HTTP endpoint, affecting versions before 1.84.0. An unauthenticated remote attacker can send a fabricated Authorization header that forces a fallback path, granting access to MCP tooling without a valid LiteLLM key, with no user interaction required.","provenance":"ai","model":"claude-haiku-5-5","generatedAt":"2026-10-31T22:21:53Z"},"cvss":{"score":8.2,"severity":"HIGH","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N","provenance":"source","from":"NVD"},"epss":{"score":0.00836,"percentile":0.57731,"date":"2026-10-31","provenance":"source"},"kev":{"dateAdded":"2026-09-02","dueDate":"2026-09-16","ransomware":false,"requiredAction":"Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.","notes":"https://github.com/BerriAI/litellm/security/advisories/GHSA-7488-6r32-c95q ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2026-59822","provenance":"source"},"vulncheckKev":{"dateAdded":"2026-07-08","exploitedFirstSeen":"2026-07-08","ransomware":false,"evidence":[{"url":"https://euvd.enisa.europa.eu/enisa/EUVD-2026-42359","date":"2026-07-08"},{"url":"https://www.linkedin.com/posts/yaarashriki_cve-2026-59821-cve-2026-59822-i-found-activity-7487129774184632320-TvsW/","date":"2026-07-26"},{"url":"https://www.wiz.io/blog/ai-infrastructure-honeypot","date":"2026-08-27"},{"url":"https://previdian.com/CVE-2026-59822","date":"2026-09-02"},{"url":"https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json","date":"2026-09-02"}],"evidenceTotal":5,"provenance":"source"},"exploited":true,"otx":{"pulseCount":34,"pulses":[{"name":"Actively_Exploited_Kev | Oct 31, 2026","url":"https://otx.alienvault.com/pulse/6ae4aefab0c2191cecd41862","created":"2026-10-30"},{"name":"Actively_Exploited_Kev | Oct 30, 2026","url":"https://otx.alienvault.com/pulse/6ae35d889ea92b4ce19c2680","created":"2026-10-29"},{"name":"Actively_Exploited_Kev | Oct 29, 2026","url":"https://otx.alienvault.com/pulse/6ae20c1db17e7057ae7d9ad1","created":"2026-10-28"},{"name":"Actively_Exploited_Kev | Oct 28, 2026","url":"https://otx.alienvault.com/pulse/6ae0ba7e0e2a97ff7b218819","created":"2026-10-27"},{"name":"Actively_Exploited_Kev | Oct 27, 2026","url":"https://otx.alienvault.com/pulse/6adf68b85c3e852f3c111d18","created":"2026-10-26"},{"name":"Actively_Exploited_Kev | Oct 24, 2026","url":"https://otx.alienvault.com/pulse/6adb740e397c3ad4799aa4cd","created":"2026-10-23"},{"name":"Actively_Exploited_Kev | Oct 23, 2026","url":"https://otx.alienvault.com/pulse/6ada236fcfba2dfa730ea482","created":"2026-10-22"},{"name":"Actively_Exploited_Kev | Oct 22, 2026","url":"https://otx.alienvault.com/pulse/6ad8d33a077cbb5cab524d80","created":"2026-10-21"},{"name":"Actively_Exploited_Kev | Oct 21, 2026","url":"https://otx.alienvault.com/pulse/6ad78130c4d1ac2be83a8b6d","created":"2026-10-20"},{"name":"Actively_Exploited_Kev | Oct 20, 2026","url":"https://otx.alienvault.com/pulse/6ad62f63c24a405a3423cc13","created":"2026-10-19"}],"provenance":"machine"},"cwes":[{"id":"CWE-287","name":"Improper Authentication"},{"id":"CWE-306","name":"Missing Authentication for Critical Functionality"}],"references":[{"url":"https://github.com/BerriAI/litellm/commit/73869f0faf7d11ee21adcb5f91b8c33a340b6c2c","tags":["Patch"]},{"url":"https://github.com/BerriAI/litellm/pull/26463","tags":["Issue Tracking","Patch"]},{"url":"https://github.com/BerriAI/litellm/releases/tag/v1.84.0","tags":["Product","Release Notes"]},{"url":"https://github.com/BerriAI/litellm/security/advisories/GHSA-7488-6r32-c95q","tags":["Mitigation","Patch","Vendor Advisory"]},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-59822","tags":["US Government Resource"]},{"url":"https://www.wiz.io/blog/ai-infrastructure-honeypot","tags":["Third Party Advisory"]}],"techniques":[{"id":"T1190","name":"Exploit Public-Facing Application","tactics":["initial-access"],"provenance":"ai","basis":"ai-mapping","bases":["ai-mapping"],"basisDetail":"claude-haiku-5-5: unauthenticated remote exploitation of public-facing endpoint","mappingType":"exploitation_technique","evidence":[{"from":"description","quote":"allowed an unauthenticated attacker to use a fabricated Authorization header","start":142,"end":218}],"model":"claude-haiku-5-5","confidence":"medium","confidenceNote":"AI-mapped from the description (quote-validated, not expert-reviewed)"},{"id":"T1078","name":"Valid Accounts","tactics":["initial-access","persistence","privilege-escalation","stealth"],"provenance":"ai","basis":"ai-mapping","bases":["ai-mapping"],"basisDetail":"claude-haiku-5-5: bypasses key validation granting access","mappingType":"primary_impact","evidence":[{"from":"description","quote":"allowing requests to reach MCP tooling without a valid LiteLLM key","start":349,"end":415}],"model":"claude-haiku-5-5","confidence":"medium","confidenceNote":"AI-mapped from the description (quote-validated, not expert-reviewed)"}],"reports":[],"affected":[{"ecosystem":"PyPI","package":"litellm","vulnerableRanges":["<1.84.0"],"patched":["1.84.0"],"from":["GHSA-7488-6r32-c95q","PYSEC-2026-3479"],"provenance":"source"}],"advisories":[{"id":"GHSA-7488-6r32-c95q","url":"https://github.com/advisories/GHSA-7488-6r32-c95q","severity":"HIGH","ecosystem":"PyPI","package":"litellm","vulnerableRanges":["<1.84.0"],"patched":["1.84.0"],"provenance":"source","from":"GHSA"}],"euvd":{"id":"EUVD-2026-42359","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-42359","exploited":true,"exploitedSince":"2026-09-02","provenance":"source"},"exploits":[],"exploitSources":{"pocGithub":{"count":1,"skipped":0,"earliest":"2026-09-03","earliestUrl":"https://github.com/HORKimhab/CVE-2026-59822","repos":[{"name":"HORKimhab/CVE-2026-59822","url":"https://github.com/HORKimhab/CVE-2026-59822","stars":0,"created":"2026-09-03"}]},"first":{"date":"2026-09-03","source":"PoC-in-GitHub","url":"https://github.com/HORKimhab/CVE-2026-59822"},"provenance":"source"},"exploitRefs":[],"flow":[{"stage":"exploitation","techniques":["T1190"],"provenance":"ai"},{"stage":"primary","techniques":["T1078"],"provenance":"ai"}],"timeline":[{"date":"2026-07-08","kind":"published","label":"Published (NVD)","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-59822","provenance":"source"},{"date":"2026-07-08","kind":"exploited-reported","label":"Exploitation first reported (VulnCheck KEV evidence)","url":"https://euvd.enisa.europa.eu/enisa/EUVD-2026-42359","provenance":"source"},{"date":"2026-09-02","kind":"kev","label":"Added to CISA KEV","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","provenance":"source"},{"date":"2026-09-02","kind":"euvd-exploited","label":"ENISA EUVD: exploited","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-42359","provenance":"source"},{"date":"2026-09-03","kind":"exploit-public","label":"First public exploit: PoC-in-GitHub","url":"https://github.com/HORKimhab/CVE-2026-59822","provenance":"source"}],"speed":{"daysToPublicExploit":57,"firstExploitFrom":"PoC-in-GitHub","daysToKev":56},"priority":{"score":65.3,"factors":[{"name":"In a KEV catalog","points":35.0,"detail":"listed in CISA KEV and VulnCheck KEV"},{"name":"Recent KEV listing","points":5.0,"detail":"added 115 days ago"},{"name":"Known ransomware use","points":0.0,"detail":"not known"},{"name":"EPSS percentile","points":11.55,"detail":"percentile 0.5773"},{"name":"Named in threat reports","points":0.0,"detail":"0 reports"},{"name":"Public exploit code","points":5.0,"detail":"1 PoC-in-GitHub repo"},{"name":"Mentioned in OTX pulses","points":3.0,"detail":"34 pulses"},{"name":"CVSS severity","points":5.74,"detail":"base score 8.2"},{"name":"End-of-life product","points":0.0,"detail":"supported or unknown"}]},"lineage":{"packageHistory":[{"cve":"CVE-2026-47101","published":"2026-05-21","fixed":"1.83.14","kev":false,"link":{"from":"CVE-2026-47101","to":"CVE-2026-59822","relation":"successor","confidence":"low","kind":"sequence","evidence":[{"kind":"version-step","provenance":"source","package":"PyPI:litellm","fromFixed":"1.83.14","toFixed":"1.84.0","daysApart":48}]}},{"cve":"CVE-2026-12773","published":"2026-06-21","fixed":"1.84.0","kev":false},{"cve":"CVE-2026-49468","published":"2026-06-22","fixed":"1.84.0","kev":false},{"cve":"CVE-2026-59822","published":"2026-07-08","fixed":"1.84.0","kev":true},{"cve":"CVE-2026-84377","published":"2026-09-02","fixed":"1.96.2","kev":false,"link":{"from":"CVE-2026-59822","to":"CVE-2026-84377","relation":"successor","confidence":"low","kind":"sequence","evidence":[{"kind":"version-step","provenance":"source","package":"PyPI:litellm","fromFixed":"1.84.0","toFixed":"1.88.6","daysApart":56}]}},{"cve":"CVE-2026-114612","published":"2026-10-22","fixed":"1.104.0rc2","kev":false}],"package":"PyPI:litellm"}}