Ghostwire

CVE-2026-5466: wolfSSL's ECCSI signature verifier `wc_VerifyEccsiHash` decodes the `r` and `s` scalars from the signature blob via...

HIGH CVSS 7.5 EPSS 0.01%

Published: April 10, 2026 | Last Modified: April 10, 2026

Description

wolfSSL's ECCSI signature verifier `wc_VerifyEccsiHash` decodes the `r` and `s` scalars from the signature blob via `mp_read_unsigned_bin` with no check that they lie in `[1, q-1]`. A crafted forged signature could verify against any message for any identity, using only publicly-known constants.

Ghostwire Analysis — What This Means Practically

Exploitation Probability (EPSS): Low — 0.01% (1th percentile)

Low exploitation probability based on current threat landscape data. Standard patching timeline is appropriate.

This analysis is generated by Ghostwire from NVD, CISA KEV, EPSS, and open-source intelligence data. Verify findings through primary sources before acting.

Security Coverage (2 articles)

References