CVE-2026-118373
LibreSSL ocspcheck through 4.4.0 Cleartext Transmission of OCSP Requests via url2host()
- State
- Published
- Severity
- 6.3 Medium
- Published
- Oct 28, 2026
- Updated
- Oct 28, 2026
- Reserved
- Oct 28, 2026
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 6.3 Medium | 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 | VulnCheck |
| 3.1 | 3.7 Low | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N | VulnCheck |
Weaknesses
- CWE-319 Cleartext Transmission of Sensitive Information
Affected Products
| Product | Versions |
|---|---|
LibreSSLOpenBSD |
|
References
- https://github.com/openbsd/src/commit/0f7039667044d1cd252cc72134e499186da4da25patch
- https://github.com/openbsd/src/blob/17a8e44328ee2505d69723a126a390a526e50370/usr.sbin/ocspcheck/http.c#L299technical-description
- LibreSSL 4.4.0 Release Notesrelease-notes
- https://github.com/libressl/portableproduct
- VulnCheck Advisory: LibreSSL ocspcheck through 4.4.0 Cleartext Transmission of OCSP Requests via url2host()third-party-advisory
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