PatchTheCVECVE-2026-118373: LibreSSL ocspcheck through 4.4.0 contains a cleartext transmission vulnerability because url2host() discards t
CVE-2026-118373 is a low-severity flaw (CVSS 3.7) affecting affected software. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
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.
Why this priority
- Remotely exploitable, no login, no user action
No fix is published yet: follow the downgrade or mitigation steps.
Risk facts
| CVSS score | 3.7 (Low) |
| Attack vector | Network (remote) |
| Attack complexity | High |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | n/a |
| CISA exploited list | No |
| Weakness | CWE-319 |
| Published | 2026-10-28 |
| Last modified | 2026-10-28 |
Last updated 2026-10-28 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Timeline
- Published CVE record published
- Updated Record last modified
Advisories and coverage
Research and news
- Vulners Bulletins: CVE-2026-118373 2026-10-28
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2026-118373?
No fixed release is listed yet. Watch the vendor advisory and apply any mitigation shown on this page.
Is CVE-2026-118373 being exploited?
CVE-2026-118373 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2026-118373 affect?
CVE-2026-118373 affects affected software. Severity is low (CVSS 3.7). 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
How urgent is CVE-2026-118373?
Priority 18/100. Remotely exploitable, no login, no user action