CVE-2026-118374
LibreSSL ocspcheck through 4.4.0 Memory Exhaustion via Unbounded OCSP HTTP Response
CVSS Score
5.9
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-770 |
| Vendor | openbsd |
| Product | libressl |
| Published | Oct 28, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H Attack Vector
Network
Attack Complexity
High
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Affected Versions
OpenBSD / LibreSSL
0 ≤ 4.4.0
References
github.com: https://github.com/openbsd/src/commit/bf5da63f53179ef423d18c56d6da89eaefb56228 github.com: https://github.com/openbsd/src/commit/de4274c56c9ace88232591d4c919d79281a8de59 github.com: https://github.com/openbsd/src/blob/f6f428241d469cf434e60b73fc834d0448f068d5/usr.sbin/ocspcheck/http.c#L419 ftp.openbsd.org: https://ftp.openbsd.org/pub/OpenBSD/LibreSSL/libressl-4.4.0-relnotes.txt github.com: https://github.com/libressl/portable vulncheck.com: https://www.vulncheck.com/advisories/libressl-ocspcheck-through-4.4.0-memory-exhaustion-via-unbounded-ocsp-http-response
Credits
Aziz Elbelaychy (Ostorlab) Frank Denis