
CVE catalog
CVE-2026-8720
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 B
- Severity
- Medium · CVSS 5.9
- Published
- Source
- [NVD] · [CVE record]
- EPSS
- 0.16% · Oct 25, 2026
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.
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Debian | wolfssl | sid | 5.9.2-1.2 | fixed |
| Debian | wolfssl | trixie | 5.7.2-0.1+deb13u2 | vulnerable |
| Debian | wolfssl | bookworm | 5.5.4-2+deb12u2 | vulnerable |
| Debian | wolfssl | bookworm-security | 5.5.4-2+deb12u3 | vulnerable |
| Cpe | wolfssl | Not reported | Not reported | vulnerable |
| Cpe | wolfssl | Not reported | 5.9.2 | fixed |
Fixed-version evidence
| Distribution | Package | Type | Release | Fixed version | Urgency | Origin | Bugs |
|---|---|---|---|---|---|---|---|
| Debian | wolfssl | source | sid | 5.9.2-1 | not yet assigned | Not reported | [1140815] |
| Debian | wolfssl | source | trixie | (unfixed) | not yet assigned | Not reported | [1140815] |
| Debian | wolfssl | source | bookworm | (unfixed) | end-of-life | Not reported | [1140815] |
| Cpe | wolfssl | cpe | Not reported | 5.9.2 | Not reported | Not reported | Not reported |
Notes
[trixie] wolfssl: Minor issue
OpenFactory catalog packages
[Debian 12 (Bookworm)]
- [libwolfssl35]Affected
Source package: [wolfssl]
Details (4)
5.5.4-2+deb12u2· amd64 · bookwormAffected
nvd · wolfssl · debian · bookworm; nvd · wolfssl · debian · 12
5.5.4-2+deb12u2· arm64 · bookwormAffected
nvd · wolfssl · debian · bookworm; nvd · wolfssl · debian · 12
5.5.4-2+deb12u3· amd64 · bookworm-securityAffected
nvd · wolfssl · debian · bookworm; nvd · wolfssl · debian · 12
5.5.4-2+deb12u3· arm64 · bookworm-securityAffected
nvd · wolfssl · debian · bookworm; nvd · wolfssl · debian · 12
- [libwolfssl-dev]Affected
Source package: [wolfssl]
Details (4)
5.5.4-2+deb12u2· amd64 · bookwormAffected
nvd · wolfssl · debian · bookworm; nvd · wolfssl · debian · 12
5.5.4-2+deb12u2· arm64 · bookwormAffected
nvd · wolfssl · debian · bookworm; nvd · wolfssl · debian · 12
5.5.4-2+deb12u3· amd64 · bookworm-securityAffected
nvd · wolfssl · debian · bookworm; nvd · wolfssl · debian · 12
5.5.4-2+deb12u3· arm64 · bookworm-securityAffected
nvd · wolfssl · debian · bookworm; nvd · wolfssl · debian · 12
[Debian 13 (Trixie)]
- [libwolfssl42t64]Affected
Source package: [wolfssl]
Details (2)
5.7.2-0.1+deb13u1· amd64 · trixieAffected
nvd · wolfssl · debian · 13
5.7.2-0.1+deb13u1· arm64 · trixieAffected
nvd · wolfssl · debian · 13
- [libwolfssl-dev]Affected
Source package: [wolfssl]
Details (2)
5.7.2-0.1+deb13u1· amd64 · trixieAffected
nvd · wolfssl · debian · 13
5.7.2-0.1+deb13u1· arm64 · trixieAffected
nvd · wolfssl · debian · 13
Observed: