VulnerabilityAnalyzed
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]`.
HIGH 7.6EPSS 0.15%
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.15%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 4.0
- 7.6 HIGHCVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.15% probability · 4th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-347
- Affected
- wolfssl/wolfssl
- Source
- facts@wolfssl.com
References
- https://github.com/wolfssl/wolfssl/pull/10102Issue Tracking
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.