CVE-2025-21701: Linux kernel · net: avoid race between device unregistration and ethnl ops
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.8 High · fixed in 5.15.0-1082.89~20.04.1 : patch Linux kernel soon.
Data as of 29 Oct 2026, 22:36 UTC
- Patch
- Available – fixed in 5.15.0-1082.89~20.04.1, 5.15.0-1087.96~20.04.1, 5.15.0-1081.90~20.04.1 +61
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 13 Feb 2025
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-7445-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7448-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7449-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7450-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7451-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7452-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7453-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7455-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7455-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7455-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-7459-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7460-1 (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.
AI-suggested
A patch addressing this vulnerability is available and included in Linux kernel versions 5.15.0-1082.89~20.04.1 and later. Users should update their systems to these fixed kernel versions or later. After updating, a system reboot is required to apply the changes. Due to ABI changes, recompilation and reinstallation of third-party kernel modules may be necessary. No additional mitigation actions are required beyond applying the official updates.
Description
CVE-2025-21701 is a race condition vulnerability in the Linux kernel's networking subsystem involving device unregistration and ethtool netlink operations. The flaw occurs when a network device is unregistered while its channel configuration is being modified, potentially leading to use-after-free or lock corruption. This issue was fixed by expanding checks to deny operations on devices that are in the process of being unregistered. The vulnerability affects multiple Linux kernel versions prior to 5.15.0-1082.89~20.04.1 and related builds. A patch is available and included in updated kernel releases.
References
- ubuntu.com/security/CVE-2025-21701 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2025-21701 (opens in a new tab)
- git.kernel.org/stable/c/12e070eb6964b341b41677fd260af5a305316a1f (opens in a new tab)
- git.kernel.org/stable/c/2f29127e94ae9fdc7497331003d6860e9551cdf3 (opens in a new tab)
- git.kernel.org/stable/c/4dc880245f9b529fa8f476b5553c799d2848b47b (opens in a new tab)
- git.kernel.org/stable/c/b382ab9b885cbb665e0e70a727f101c981b4edf3 (opens in a new tab)
- ubuntu.com/security/notices/USN-7445-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7448-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7449-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7450-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7451-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7452-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7453-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7455-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7455-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7455-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-7459-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7460-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7449-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7455-4 (opens in a new tab)