CVE-2026-118373

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.

CVSS v3 3.7 LOW

3.7^/10

CVSS v3 : LOW

Vector :

Exploitability : 2.2 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

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/17a8e44328ee2505d69723a126a390a526e50370/usr.sbin/ocspcheck/http.c#L299
https://github.com/openbsd/src/commit/0f7039667044d1cd252cc72134e499186da4da25
https://www.vulncheck.com/advisories/libressl-ocspcheck-through-4.4.0-cleartext-transmission-of-ocsp-requests-via-url2host

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-2026-118373

Mitre link : CVE-2026-118373

CVE.ORG link : CVE-2026-118373

JSON object : View

Products Affected

No product.

CWE

CWE-319

Cleartext Transmission of Sensitive Information

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