CVE-2026-43456: Linux kernel · bonding: fix type confusion in bond_setup_by_slave()
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.8 High · fixed in 5.4.0-1165.176~18.04.1 : patch Linux kernel soon.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 8% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 5.4.0-1165.176~18.04.1, 5.4.0-1170.176~18.04.1, 5.4.0-1168.178~18.04.1 +51
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 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
Upgrade to a fixed release listed under Affected software.
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?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-gcppkg:deb/ubuntu/linux-gcp?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 fix is implemented in the bonding driver to prevent type confusion by using wrapper functions for header operations. Users should update to the patched kernel versions as provided by their Linux distribution vendors. No additional mitigations are indicated by the vendor advisory.
Description
A type confusion vulnerability in the Linux kernel bonding driver was fixed. The issue occurred when a non-Ethernet device (e.g., GRE tunnel) was enslaved to a bond device, causing the bond device to inherit header operations from the slave device improperly. This led to kernel crashes due to incorrect private data access. The fix introduces wrapper functions in the bonding driver to delegate header operations correctly, preventing type confusion and crashes.
References
- ubuntu.com/security/CVE-2026-43456 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-43456 (opens in a new tab)
- git.kernel.org/linus/950803f7254721c1c15858fbbfae3deaaeeecb11 (opens in a new tab)
- git.kernel.org/stable/c/6ac890f1d60ac3707ee8dae15a67d9a833e49956 (opens in a new tab)
- git.kernel.org/stable/c/950803f7254721c1c15858fbbfae3deaaeeecb11 (opens in a new tab)
- git.kernel.org/stable/c/95597d11dc8bddb2b9a051c9232000bfbb5e43ba (opens in a new tab)
- git.kernel.org/stable/c/9baf26a91565b7bb2b1d9f99aaf884a2b28c2f6d (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)
- ubuntu.com/security/notices/USN-8595-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8619-1 (opens in a new tab)