CVE-2026-118374

high

Description

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.

References

https://www.vulncheck.com/advisories/libressl-ocspcheck-through-4.4.0-memory-exhaustion-via-unbounded-ocsp-http-response

https://github.com/openbsd/src/commit/de4274c56c9ace88232591d4c919d79281a8de59

https://github.com/openbsd/src/commit/bf5da63f53179ef423d18c56d6da89eaefb56228

https://github.com/openbsd/src/blob/f6f428241d469cf434e60b73fc834d0448f068d5/usr.sbin/ocspcheck/http.c#L419

https://github.com/libressl/portable

https://ftp.openbsd.org/pub/OpenBSD/LibreSSL/libressl-4.4.0-relnotes.txt

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-111550

Details

Source: Mitre, NVD

Published: 2026-10-28

Updated: 2026-10-28

Risk Information

CVSS v2

Base Score: 5.4

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

Severity: Medium

CVSS v3

Base Score: 5.9

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

Severity: Medium

CVSS v4

Base Score: 8.2

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

Severity: High