CVE-2026-43457: Linux kernel · mctp: i2c: fix skb memory leak in receive path
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 5.5 Medium · patch available : update Linux kernel when convenient.
Data as of 26 Oct 2026, 14:05 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 1% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 8 May 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: 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 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde@7.0.0-1008.8?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 25.10linuxpkg:deb/ubuntu/linux@6.17.0-40.40?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-awspkg:deb/ubuntu/linux-aws@6.17.0-1019.19?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-azurepkg:deb/ubuntu/linux-azure@6.17.0-1020.20?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-azure-fdepkg:deb/ubuntu/linux-azure-fde@6.17.0-1017.17?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-gcppkg:deb/ubuntu/linux-gcp@6.17.0-1020.22?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A patch is available and should be applied to affected Linux kernel versions. The Ubuntu security advisory USN-8567-1 provides updated kernel packages that fix this issue. Systems running affected versions should upgrade to the fixed versions to remediate the vulnerability.
Description
A memory leak vulnerability in the Linux kernel's MCTP I2C receive path was fixed. When 'midev->allow_rx' is false, the newly allocated socket buffer (skb) was not freed properly, causing a memory leak. This issue has been addressed in updated Linux kernel versions.
References
- ubuntu.com/security/CVE-2026-43457 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-43457 (opens in a new tab)
- git.kernel.org/linus/e3f5e0f22cfc2371e7471c9fd5b4da78f9df7c69 (opens in a new tab)
- git.kernel.org/stable/c/0fb2adbdd5c03e8c9ebcdc48afd414b2724c85eb (opens in a new tab)
- git.kernel.org/stable/c/1b1be322342a6b0085bf6ee52235e5ac9834ec25 (opens in a new tab)
- git.kernel.org/stable/c/1ec54187e1aa40a4cfa2b265e9a311179f24b98d (opens in a new tab)
- git.kernel.org/stable/c/9f81be2ab9d8e4744871bfb3e868ef413413829f (opens in a new tab)
- git.kernel.org/stable/c/d7900a43b0a314a645ca0a2adf45928dbc7001f4 (opens in a new tab)
- git.kernel.org/stable/c/e3f5e0f22cfc2371e7471c9fd5b4da78f9df7c69 (opens in a new tab)
- ubuntu.com/security/notices/USN-8567-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8574-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8574-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8595-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8596-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8595-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8606-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8607-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8608-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8609-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8574-3 (opens in a new tab)