---
id: CVE-2026-118374
title: >-
  LibreSSL ocspcheck through 4.4.0 Memory Exhaustion via Unbounded OCSP HTTP
  Response
summary: >-
  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 O…
severity: medium
cvss: 5.9
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H'
cvssSource: cna
cwe:
  - CWE-770
vendor: OpenBSD
product: LibreSSL
affected:
  - LibreSSL <= 4.4.0
published: '2026-10-28'
updated: '2026-10-28'
sourceUpdated: '2026-10-28T02:03:22.183Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-118374'
references:
  - url: >-
      https://github.com/openbsd/src/commit/bf5da63f53179ef423d18c56d6da89eaefb56228
  - url: >-
      https://github.com/openbsd/src/commit/de4274c56c9ace88232591d4c919d79281a8de59
  - url: >-
      https://github.com/openbsd/src/blob/f6f428241d469cf434e60b73fc834d0448f068d5/usr.sbin/ocspcheck/http.c#L419
  - url: 'https://ftp.openbsd.org/pub/OpenBSD/LibreSSL/libressl-4.4.0-relnotes.txt'
    label: LibreSSL 4.4.0 Release Notes
  - url: 'https://github.com/libressl/portable'
  - url: >-
      https://www.vulncheck.com/advisories/libressl-ocspcheck-through-4.4.0-memory-exhaustion-via-unbounded-ocsp-http-response
    label: >-
      VulnCheck Advisory: LibreSSL ocspcheck through 4.4.0 Memory Exhaustion via
      Unbounded OCSP HTTP Response
tags:
  - cve.org
ingestedAt: '2026-10-28T03:02:57.623Z'
---

## Overview

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.

## Affected

- `LibreSSL <= 4.4.0`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.