{"id":"CVE-2026-119559","title":"OpenLiteSpeed through 1.9.4 mTLS Bypass via HTTP/3 SNI and Host Mismatch","summary":"OpenLiteSpeed through 1.9.4 contains an authentication bypass vulnerability that allows unauthenticated remote attackers to evade virtual host client certificate requirements over HTTP/3. Because QuicStream inherits a verifyContext() imp…","severity":"medium","cvss":5.9,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N","cvssSource":"cna","cwe":["CWE-295"],"vendor":"litespeedtech","product":"openlitespeed","affected":["openlitespeed <= 1.9.4"],"published":"2026-10-30","updated":"2026-10-30","sourceUpdated":"2026-10-30T11:31:08.276Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-119559","references":[{"url":"https://github.com/litespeedtech/openlitespeed/blob/v1.9.4/src/http/httpsession.cpp#L1665-L1672"},{"url":"https://github.com/litespeedtech/openlitespeed/blob/v1.9.4/src/sslpp/hiocrypto.h#L49-L50"},{"url":"https://github.com/litespeedtech/openlitespeed/blob/v1.9.4/src/quic/quicstream.h#L33-L37"},{"url":"https://abraxaslabs.tech/research/openlitespeed-h3-mtls-verifycontext"},{"url":"https://github.com/litespeedtech/openlitespeed"},{"url":"https://www.vulncheck.com/advisories/openlitespeed-through-1.9.4-mtls-bypass-via-http-3-sni-and-host-mismatch","label":"VulnCheck Advisory: OpenLiteSpeed through 1.9.4 mTLS Bypass via HTTP/3 SNI and Host Mismatch"}],"tags":["cve.org"],"epss":0.00289,"epssPercentile":0.21538,"ingestedAt":"2026-11-03T11:43:15.774Z","slug":"CVE-2026-119559","body":"## Overview\n\nOpenLiteSpeed through 1.9.4 contains an authentication bypass vulnerability that allows unauthenticated remote attackers to evade virtual host client certificate requirements over HTTP/3. Because QuicStream inherits a verifyContext() implementation that always returns true, attackers can present a non-mTLS host's SNI with a protected Host header to access protected content.\n\n## Affected\n\n- `openlitespeed <= 1.9.4`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":33,"depthScoreParts":{"impact":32.5,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}