CVE-2026-5466

EUVD-2026-21291
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.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
8.1 HIGH
ADJACENT_NETWORK
LOW
NONE
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Base Score
CVSS 3.x
EPSS Score
Percentile: Unknown
Affected Products (NVD)
VendorProductVersion
wolfsslwolfssl
𝑥
< 5.9.1
𝑥
= Vulnerable software versions
Debian logo
Debian Releases
Debian Product
Codename
wolfssl
bookworm
no-dsa
bullseye
postponed
forky
5.9.1-0.1
fixed
sid
5.9.1-0.1
fixed
trixie
no-dsa
Ubuntu logo
Ubuntu Releases
Ubuntu Product
Codename
wolfssl
bionic
needs-triage
focal
needs-triage
jammy
needs-triage
noble
needs-triage
questing
needs-triage
resolute
needs-triage
xenial
ignored
Common Weakness Enumeration
References
https://github.com/wolfssl/wolfssl/pull/10102