CVE-2026-8720
highpriority · track · 30EPSS 0.002 · 5 %ileEUUSEPSS · scored 2026-10-27
wc_Blake2bHmacFinal and wc_Blake2sHmacFinal discard the message when the key length exceeds the block size, producing a MAC that is independent of the input. When the supplied key is longer than the BLAKE2 block size the key-hashing branch reinitialized the running hash state, discarding the accumulated message data, so the resulting MAC depended only on the key and not on the message being authenticated. This bug is specific to the HMAC-BLAKE2 APIs that were added in wolfSSL version 5.9.0.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–high · 2.1–7.5
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (2)
Products and version ranges known to be affected.
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (7)
External citations — patches, advisories, analysis.
- https://github.com/wolfSSL/wolfssl/pull/10447cnnvd
- https://www.wolfssl.com/docs/security-vulnerabilities/cnnvd
- https://www.wolfssl.com/download/Patchcnnvd
- https://github.com/wolfSSL/wolfssl/pull/10447enisa_euvd
- https://www.wolfssl.com/docs/security-vulnerabilities/enisa_euvd
- https://github.com/wolfSSL/wolfssl/pull/10447Issue TrackingPatchnvd
- https://www.wolfssl.com/docs/security-vulnerabilities/Vendor Advisorynvd
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