ReviewCritical

CVE-2026-57826

the affected product

An issue was discovered in openHiTLS 0.2.0 through 0.3.2. In the X.509 certificate chain verification, the basic constraints extension and CA flag processing of intermediate CAs are only verified for v3 certificates, and v1/v2 certificates are ignored.

CVSS
9.8
EPSS
-
- percentile
CISA KEV
Not listed
Published
2026.08.19
PRIORITY ASSESSMENT

Review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV
Exploit probability-
Technical severityCVSS 9.8

Vulnerability overview

An issue was discovered in openHiTLS 0.2.0 through 0.3.2. In the X.509 certificate chain verification, the basic constraints extension and CA flag processing of intermediate CAs are only verified for v3 certificates, and v1/v2 certificates are ignored.

Affected product and versions

Product
the affected product
Affected versions
See the vendor advisory and NVD configuration data
Fixed versions
No verified fixed-version field is available yet

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide
  1. 1
    Identify

    Confirm that the affected product and an affected version are present.

  2. 2
    Prioritize

    Combine exploitation signals with asset exposure and business criticality.

  3. 3
    Remediate

    Follow the vendor advisory or supported update path and preserve rollback options.

  4. 4
    Verify

    Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE
CWE-295