CVE-2026-119559

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.

CVSS v3 5.9 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://abraxaslabs.tech/research/openlitespeed-h3-mtls-verifycontext
https://github.com/litespeedtech/openlitespeed
https://github.com/litespeedtech/openlitespeed/blob/v1.9.4/src/http/httpsession.cpp#L1665-L1672
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/sslpp/hiocrypto.h#L49-L50
https://www.vulncheck.com/advisories/openlitespeed-through-1.9.4-mtls-bypass-via-http-3-sni-and-host-mismatch

Configurations

No configuration.

History

30 Oct 2026, 12:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-30 12:16

Updated : 2026-10-30 19:23

NVD link : CVE-2026-119559

Mitre link : CVE-2026-119559

CVE.ORG link : CVE-2026-119559

JSON object : View

Products Affected

No product.

CWE

CWE-295

Improper Certificate Validation

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