CVE-2026-5466
Published:April 10, 2026
Updated:April 22, 2026
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.
Affected Packages
https://github.com/wolfSSL/wolfssl.git (GITHUB):
Affected version(s) >=v0.5 <v5.9.1-stableFix Suggestion:
Update to version v5.9.1-stableRelated Resources (1)
Do you need more information?
Contact UsCVSS v4
Base Score:
7.6
Attack Vector
ADJACENT
Attack Complexity
LOW
Attack Requirements
PRESENT
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
HIGH
Vulnerable System Integrity
HIGH
Vulnerable System Availability
NONE
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
8.1
Attack Vector
ADJACENT
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
NONE
Weakness Type (CWE)
Improper Verification of Cryptographic Signature
EPSS
Base Score:
0.01
