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.
Advisories
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Fixes
Solution
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Workaround
No workaround given by the vendor.
References
History
Fri, 26 Jun 2026 11:30:00 +0000
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ssvc
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Fri, 26 Jun 2026 01:30:00 +0000
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Wolfssl
Wolfssl wolfssl |
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| Vendors & Products |
Wolfssl
Wolfssl wolfssl |
Thu, 25 Jun 2026 21:30:00 +0000
| Type | Values Removed | Values Added |
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| Description | 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. | |
| Title | HMAC-BLAKE2 final discards message when key length exceeds block size | |
| Weaknesses | CWE-354 | |
| References |
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| Metrics |
cvssV4_0
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Projects
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Status: PUBLISHED
Assigner: wolfSSL
Published:
Updated: 2026-06-26T10:35:31.343Z
Reserved: 2026-05-15T22:33:26.158Z
Link: CVE-2026-8720
Updated: 2026-06-26T10:35:15.134Z
No data.
No data.
OpenCVE Enrichment
Updated: 2026-06-26T01:15:04Z
Weaknesses