CVE-2026-118373

LibreSSL ocspcheck through 4.4.0 Cleartext Transmission of OCSP Requests via url2host()

Published Oct 28, 2026 CVSS 4.0 · 6.3 Medium EPSS < 1% KEV · Not listed
Description
LibreSSL ocspcheck through 4.4.0 contains a cleartext transmission vulnerability because url2host() discards the OCSP URL scheme and http_alloc() only selects TLS for port 443. On-path network attackers can read OCSP requests sent to https responder URLs on non-443 ports, exposing certificate serial numbers, issuer hashes, and nonces.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description LibreSSL ocspcheck through 4.4.0 contains a cleartext transmission vulnerability because url2host() discards the OCSP URL scheme and http_alloc() only selects TLS for port 443. On-path network attackers can read OCSP requests sent to https responder URLs on non-443 ports, exposing certificate serial numbers, issuer hashes, and nonces.
Title LibreSSL ocspcheck through 4.4.0 Cleartext Transmission of OCSP Requests via url2host()
First Time appeared Openbsd
Openbsd libressl
Weaknesses CWE-319
CPEs cpe:2.3:a:openbsd:libressl:*:*:*:*:*:*:*:*
Vendors & Products Openbsd
Openbsd libressl
References
Metrics cvssV3_1

{'score': 3.7, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N'}

cvssV4_0

{'score': 6.3, 'vector': 'CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
VulnCheck
Published
Updated
Nov 5, 2026, 3:43 PM
Reserved
Oct 28, 2026, 1:19 AM
Status
Deferred
Published
Oct 28, 2026, 3:17 AM
Modified
Nov 5, 2026, 4:17 PM