VDB

CVE-2026-87866

CVE-2026-87866 PUBLISHED

Reported by curl · Published October 20, 2026

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.

EPSS 0.51% · 43.5th percentile

Risk Scores

EPSS Score
0.51%
43.5th percentile

Affected Products

VendorProductVersions
curlcurl8.22.0, 8.21.0, 8.20.0
alpinecurl0
curlcurl8.22.0, 8.21.0, 8.20.0

Timeline

  • CVE Published
  • Oct 14, 2026 PoC Published
  • Oct 21, 2026 EPSS Score
  • Oct 25, 2026 EPSS Score
  • Oct 27, 2026 EPSS Score
  • Oct 30, 2026 EPSS Score

References

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