CVE-2025-68191: Linux kernel · udp_tunnel: use netdev_warn() instead of netdev_WARN()
Affects Linux kernelSource GCVE Database
Not known to be exploited · fixed in 5.15.0-1103.110~20.04.1 : update Linux kernel when convenient.
Data as of 26 Oct 2026, 12:55 UTC
Rated by Threat Radar · No CVSS score from NVD or the CNA
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 10% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 5.15.0-1103.110~20.04.1, 5.15.0-1110.119~20.04.1, 5.15.0-1114.123~20.04.1 +66
Exploitation evidence
Disclosed: evidence found.
CVE published 16 Dec 2025
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 25.10linuxpkg:deb/ubuntu/linux@6.17.0-14.14?arch=source&distro=questingOther threats | Affected
| Fixed in
|
Ubuntu 25.10linux-awspkg:deb/ubuntu/linux-aws@6.17.0-1007.7?arch=source&distro=questingOther threats | Affected
| Fixed in
|
Ubuntu 25.10linux-azurepkg:deb/ubuntu/linux-azure@6.17.0-1008.8?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@6.17.0-1007.7?arch=source&distro=questingOther threats | Affected
| Fixed in
|
Ubuntu 25.10linux-oraclepkg:deb/ubuntu/linux-oracle@6.17.0-1007.7?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 update the Linux kernel to a fixed version. The affected versions are prior to 5.15.0-1103.110~20.04.1, 5.15.0-1110.119~20.04.1, 5.15.0-1114.123~20.04.1, 5.15.0-1103.112~20.04.1, and 5.15.0-173.183~20.04.1. Applying the official kernel updates from the vendor (Ubuntu) will remediate this issue.
Description
A vulnerability in the Linux kernel's udp_tunnel component was resolved by replacing netdev_WARN() with netdev_warn(). The issue involved netdev_WARN() generating kernel warnings with backtraces for normal runtime errors such as memory allocation failures, which are not actual kernel bugs. This change prevents misleading kernel warnings for expected error conditions.
References
- ubuntu.com/security/CVE-2025-68191 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2025-68191 (opens in a new tab)
- git.kernel.org/linus/dc2f650f7e6857bf384069c1a56b2937a1ee370d (opens in a new tab)
- git.kernel.org/stable/c/087f1ed450dc6e7e49ffbbbe5b78be1218c6d5e0 (opens in a new tab)
- git.kernel.org/stable/c/3c3b148bf8384c8a787753cf20abde1c5731f97f (opens in a new tab)
- git.kernel.org/stable/c/45e4e4a8772fa1c5f6f38e82b732b3a9d8137af4 (opens in a new tab)
- git.kernel.org/stable/c/51b3033088f0420b19027e3d54cd989b6ebd987e (opens in a new tab)
- git.kernel.org/stable/c/7758ec35ff3e9a31558eda4f0f9eb0ddfa78a8ba (opens in a new tab)
- git.kernel.org/stable/c/c018a87942bf1607aeebf8dba5a210ca9a09a0fd (opens in a new tab)
- git.kernel.org/stable/c/dc2f650f7e6857bf384069c1a56b2937a1ee370d (opens in a new tab)
- ubuntu.com/security/notices/USN-8029-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8030-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8029-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8048-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8029-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8095-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8096-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8100-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8095-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8096-2 (opens in a new tab)