CVE-2026-119559

high

Description

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() implementation that always returns true, attackers can present a non-mTLS host's SNI with a protected Host header to access protected content.

References

https://www.vulncheck.com/advisories/openlitespeed-through-1.9.4-mtls-bypass-via-http-3-sni-and-host-mismatch

https://github.com/litespeedtech/openlitespeed/blob/v1.9.4/src/sslpp/hiocrypto.h#L49-L50

https://github.com/litespeedtech/openlitespeed/blob/v1.9.4/src/quic/quicstream.h#L33-L37

https://github.com/litespeedtech/openlitespeed/blob/v1.9.4/src/http/httpsession.cpp#L1665-L1672

https://github.com/litespeedtech/openlitespeed

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-113824

https://abraxaslabs.tech/research/openlitespeed-h3-mtls-verifycontext

Details

Source: Mitre, NVD

Published: 2026-10-30

Updated: 2026-10-30

Risk Information

CVSS v2

Base Score: 5.4

Vector: CVSS2#AV:N/AC:H/Au:N/C:C/I:N/A:N

Severity: Medium

CVSS v3

Base Score: 5.9

Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

Severity: Medium

CVSS v4

Base Score: 8.2

Vector: CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N

Severity: High

EPSS

EPSS: 0.00289