CVE-2026-5466

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.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.2

Attack Vector ADJACENT_NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/wolfssl/wolfssl/pull/10102	Issue Tracking

Configurations

Configuration 1 (hide)

cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:*

History

29 Apr 2026, 13:49

Type	Values Removed	Values Added
CPE		cpe:2.3:a:wolfssl:wolfssl::::::::
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 8.1
References	~~() https://github.com/wolfssl/wolfssl/pull/10102 -~~	() https://github.com/wolfssl/wolfssl/pull/10102 - Issue Tracking
First Time		Wolfssl Wolfssl wolfssl

10 Apr 2026, 04:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-04-10 04:17

Updated : 2026-04-29 13:49

NVD link : CVE-2026-5466

Mitre link : CVE-2026-5466

CVE.ORG link : CVE-2026-5466

JSON object : View

Products Affected

wolfssl

wolfssl

CWE

CWE-347

Improper Verification of Cryptographic Signature

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