CVE-2026-87866

wolfSSL public-key pinning bypass

State
Published
Severity
9.1 Critical
Published
Oct 20, 2026
Updated
Oct 29, 2026
Reserved
Sep 9, 2026

Read the record on cve.org

Description

When built with wolfSSL, curl can successfully validate a pinned public key hash against a key the TLS peer does not possess. During the TLS handshake, wolfSSL validates the connection, but curl's subsequent re-parsing of the same certificate - tricked by a manipulated validity length field - extracts and matches a different embedded key, incorrectly authorizing the pinned public key.

Scores

CVSSScoreVectorSource
3.19.1 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:NCISA-ADP

Weaknesses

  • CWE-295 Improper Certificate Validation

Affected Products

ProductVersions
curlcurl
  • 8.22.0 through 8.22.0Affected
  • 8.21.0 through 8.21.0Affected
  • 8.20.0 through 8.20.0Affected
  • 8.19.0 through 8.19.0Affected
  • 8.18.0 through 8.18.0Affected
  • 8.17.0 through 8.17.0Affected
  • 8.16.0 through 8.16.0Affected
  • 8.15.0 through 8.15.0Affected
  • 8.14.1 through 8.14.1Affected
  • 8.14.0 through 8.14.0Affected
  • 8.13.0 through 8.13.0Affected
  • 8.12.1 through 8.12.1Affected
  • 8.12.0 through 8.12.0Affected
  • 8.11.1 through 8.11.1Affected
  • 8.11.0 through 8.11.0Affected
  • 8.10.1 through 8.10.1Affected
  • 8.10.0 through 8.10.0Affected
  • 8.9.1 through 8.9.1Affected
  • 8.9.0 through 8.9.0Affected
  • 8.8.0 through 8.8.0Affected
  • 8.7.1 through 8.7.1Affected
  • 8.7.0 through 8.7.0Affected
  • 8.6.0 through 8.6.0Affected
  • 8.5.0 through 8.5.0Affected
  • 8.4.0 through 8.4.0Affected
  • and 75 more versions

References

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