CVE-2026-43427: Linux kernel · usb: class: cdc-wdm: fix reordering issue in read code path
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.1 High · patch available : patch Linux kernel soon.
Data as of 26 Oct 2026, 14:05 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 2% 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:H/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
An official fix is available and should be applied. The vulnerability has been resolved in updated Linux kernel packages. Users should update to the fixed kernel versions provided by their distribution. No additional mitigation is required beyond applying the official patch.
Description
A vulnerability in the Linux kernel's usb: class: cdc-wdm driver was fixed to address a reordering issue in the read code path. Due to compiler optimizations or CPU out-of-order execution, a memory update could be reordered, causing the read function to access uninitialized memory. This violates kernel memory model data race rules and could lead to memory safety issues. The issue has been resolved by using WRITE_ONCE and memory barriers to enforce correct ordering.
References
- ubuntu.com/security/CVE-2026-43427 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-43427 (opens in a new tab)
- git.kernel.org/linus/8df672bfe3ec2268c2636584202755898e547173 (opens in a new tab)
- git.kernel.org/stable/c/170e8daca24da6edb4be82ab01abf44e87af387b (opens in a new tab)
- git.kernel.org/stable/c/276aef0fd2b92f41b920ac891c72cadeee957934 (opens in a new tab)
- git.kernel.org/stable/c/4ee3062bf2c9a722afef429826e8607eaf3fc6a0 (opens in a new tab)
- git.kernel.org/stable/c/638328ca9c17ae6511ad62198c57bae32ffa3c91 (opens in a new tab)
- git.kernel.org/stable/c/67ed312124bb1b61858778ac0b985b48961c862a (opens in a new tab)
- git.kernel.org/stable/c/8df672bfe3ec2268c2636584202755898e547173 (opens in a new tab)
- git.kernel.org/stable/c/c8fa96ed021923dae147bcd9f9205b8df7b82360 (opens in a new tab)
- git.kernel.org/stable/c/e3c874b05901dc519054b5107d16620e6d2b5fea (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-8575-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8576-1 (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-8575-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8576-2 (opens in a new tab)