{"apiVersion":"1.0","identifier":"CVE-2026-63382","description":"Libevent is an event notification library. Prior to 2.1.13 and 2.2.2-alpha, the libevent evhttp parser in http.c inconsistently handles duplicate Transfer-Encoding headers, comma-separated Transfer-Encoding values, and bare line feeds in chunked framing. evhttp_find_header can select only the first header, evhttp_check_transfer_encoding_ was absent so the previous whole-string comparison fails to recognize valid lists ending in chunked, and evhttp_handle_chunked_read uses EVBUFFER_EOL_CRLF rather than EVBUFFER_EOL_CRLF_STRICT, accepting bare LF chunk terminators. When libevent is deployed behind a proxy that frames the same request differently, an unauthenticated remote attacker can desynchronize request boundaries and smuggle a second request, potentially bypassing access controls or poisoning caches. This issue is fixed in versions 2.1.13 and 2.2.2-alpha.","publishedAt":"2026-08-20T18:16:35","lastModifiedAt":"2026-08-20T20:17:45","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-63382","cvssScore":9.2,"cvssVector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:L/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","epssProbability":0.00587,"riskScore":0.97,"affectedProduct":"libevent","affectedVersions":"<2.1.13, <2.2.2-alpha","vulnerabilityType":"Library","operatingSystems":[],"links":{"self":"https://www.redsauce.net/api/cves/CVE-2026-63382","webPages":{"es":"https://www.redsauce.net/es/cves/CVE-2026-63382","en":"https://www.redsauce.net/en/cves/CVE-2026-63382","fr":"https://www.redsauce.net/fr/cves/CVE-2026-63382","pt":"https://www.redsauce.net/pt/cves/CVE-2026-63382","de":"https://www.redsauce.net/de/cves/CVE-2026-63382","sk":"https://www.redsauce.net/sk/cves/CVE-2026-63382","el":"https://www.redsauce.net/el/cves/CVE-2026-63382"},"source":"https://nvd.nist.gov/vuln/detail/CVE-2026-63382"}}