CVE-2026-118374

LibreSSL ocspcheck through 4.4.0 contains a memory exhaustion vulnerability that allows malicious OCSP responders to exhaust memory by sending unbounded HTTP responses. Attackers controlling the responder or intercepting plain HTTP AIA OCSP traffic can stream endless headers or body data to http_head_read() and http_body_read(), denying certificate status checks.

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 NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://ftp.openbsd.org/pub/OpenBSD/LibreSSL/libressl-4.4.0-relnotes.txt
https://github.com/libressl/portable
https://github.com/openbsd/src/blob/f6f428241d469cf434e60b73fc834d0448f068d5/usr.sbin/ocspcheck/http.c#L419
https://github.com/openbsd/src/commit/bf5da63f53179ef423d18c56d6da89eaefb56228
https://github.com/openbsd/src/commit/de4274c56c9ace88232591d4c919d79281a8de59
https://www.vulncheck.com/advisories/libressl-ocspcheck-through-4.4.0-memory-exhaustion-via-unbounded-ocsp-http-response

Configurations

No configuration.

History

28 Oct 2026, 03:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-28 03:17

Updated : 2026-10-28 14:49

NVD link : CVE-2026-118374

Mitre link : CVE-2026-118374

CVE.ORG link : CVE-2026-118374

JSON object : View

Products Affected

No product.

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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