CVE-2024-56681: Linux kernel · crypto: bcm – add error check in the ahash_hmac_init function
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.8 High · fixed in 5.4.0-1142.152~18.04.1 : patch Linux kernel soon.
Data as of 29 Oct 2026, 22:35 UTC
- Patch
- Available – fixed in 5.4.0-1142.152~18.04.1, 5.4.0-1147.154~18.04.1, 5.4.0-1145.154~18.04.1 +82
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 28 Dec 2024
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Patches and advisories
- ubuntu.com/security/notices/USN-7276-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7277-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7310-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7387-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7388-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7389-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7390-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7387-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7387-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-7391-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7392-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7393-1 (opens in a new tab)
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 24.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-azure-6.11pkg:deb/ubuntu/linux-azure-6.11?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-azure-nvidiapkg:deb/ubuntu/linux-azure-nvidia?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
In the Linux kernel, the following vulnerability has been resolved: crypto: bcm - add error check in the ahash_hmac_init function The ahash_init functions may return fails. The ahash_hmac_init should not return ok when ahash_init returns error. For an example, ahash_init will return -ENOMEM when allocation memory is error.
References
- ubuntu.com/security/CVE-2024-56681 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2024-56681 (opens in a new tab)
- git.kernel.org/linus/19630cf57233e845b6ac57c9c969a4888925467b (opens in a new tab)
- git.kernel.org/stable/c/05f0a3f5477ecaa1cf46448504afe9e7c2e96fcc (opens in a new tab)
- git.kernel.org/stable/c/19630cf57233e845b6ac57c9c969a4888925467b (opens in a new tab)
- git.kernel.org/stable/c/28f8ffa945f7d7150463e15097ea73b19529d6f5 (opens in a new tab)
- git.kernel.org/stable/c/4ea3e3b761e371102bb1486778e2f8dbc9e37413 (opens in a new tab)
- git.kernel.org/stable/c/75e1e38e5d80d6d9011b7322698ffba3dd3db30a (opens in a new tab)
- git.kernel.org/stable/c/8f1a9a960b1107bd0e0ec3736055f5ed0e717edf (opens in a new tab)
- git.kernel.org/stable/c/ae5253313e0ea5f00c06176074592b7f493c8546 (opens in a new tab)
- git.kernel.org/stable/c/bba9e38c5ad41d0a88b22a59e5b6dd3e31825118 (opens in a new tab)
- git.kernel.org/stable/c/ee36db8e8203420e6d5c42eb9428920c2fc36532 (opens in a new tab)
- ubuntu.com/security/notices/USN-7276-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7277-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7310-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7387-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7388-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7389-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7390-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7387-2 (opens in a new tab)