תיאור (מקור, אנגלית)
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.
קישורים8
- github.com/libevent/libevent/commit/10abb34b8dc3e1184de315dd26…
- github.com/libevent/libevent/commit/5119ceb00557bf007f9065709e…
- github.com/libevent/libevent/commit/83ba67373032334559b82409db…
- github.com/libevent/libevent/commit/ac38703b2d312200c4f967f029…
- github.com/libevent/libevent/releases/tag/release-2.1.13-stable
- github.com/libevent/libevent/releases/tag/release-2.2.2-alpha
- github.com/libevent/libevent/security/advisories/GHSA-q39v-w2g…
- github.com/libevent/libevent/security/advisories/GHSA-q39v-w2g…
מדדים
- CVSS 4.0
-
9.2
CRITICAL
מקור הציון: CNA
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 - EPSS — סבירות ניצול
- 2% אחוזון 81 · נכון ל-10 בנובמבר 2026
- CWE
- CWE-444
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