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.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| wolfSSL | wolfSSL | 5.9.0 – ≤ 5.9.1 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 13 | wolfssl | No fix yet | — |
| Debian 12 | wolfssl | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | wolfssl | No fix yet | — |
| Ubuntu 26.04 LTS | wolfssl | No fix yet | — |
| Ubuntu 25.10 | wolfssl | No fix yet | — |
| Ubuntu 24.04 LTS | wolfssl | No fix yet | — |
| Ubuntu 22.04 LTS | wolfssl | No fix yet | — |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | wolfssl | No fix yet | — |
| Ubuntu 18.04 LTS | wolfssl | No fix yet | — |
| Ubuntu 16.04 LTS | wolfssl | No fix yet | — |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | wolfssl | 5.9.2-r0 | — |