CVE-2026-72297: Linux kernel · net: atm: reject out-of-range traffic classes in QoS validation
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.1 High · fixed in 5.15.0-1117.124~20.04.1 : patch Linux kernel soon.
Data as of 28 Oct 2026, 00:58 UTC
- Patch
- Available – fixed in 5.15.0-1117.124~20.04.1, 5.15.0-1123.132~20.04.1, 5.15.0-1122.131~20.04.1 +56
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 15 Aug 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.
Patches and advisories
- ubuntu.com/security/notices/USN-8876-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8878-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8879-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8877-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8875-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8888-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8889-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8887-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8886-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8888-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8887-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8875-2 (opens in a new tab)
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-gkepkg:deb/ubuntu/linux-gke?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
In the Linux kernel, the following vulnerability has been resolved: net: atm: reject out-of-range traffic classes in QoS validation Reject ATM traffic classes above ATM_ANYCLASS in check_tp(). SO_ATMQOS stores the supplied QoS after check_qos() succeeds, so accepting larger values leaves invalid traffic_class values in vcc->qos. That bad state later reaches pvc_info(), which indexes class_name[] with vcc->qos.{rx,tp}.traffic_class. Values above ATM_ANYCLASS cause an out-of-bounds read when /proc/net/atm/pvc is read. Tighten the existing QoS validation so invalid traffic_class values are rejected at the point where user supplied QoS is accepted.
References
- ubuntu.com/security/CVE-2026-72297 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-72297 (opens in a new tab)
- git.kernel.org/linus/cdf19f380e46192e7084be559638aab1f6ed86a2 (opens in a new tab)
- git.kernel.org/stable/c/15444b57fdc6fc3f3e22a87f791ae5be81e6ecf5 (opens in a new tab)
- git.kernel.org/stable/c/1a6dda72455b399ce9c1a12695471dc4d5c61add (opens in a new tab)
- git.kernel.org/stable/c/2b3e241729e87afed13ac0f666472d5d6ca42e87 (opens in a new tab)
- git.kernel.org/stable/c/367acd288bc6255e247cb1a1efbf5c6567cab423 (opens in a new tab)
- git.kernel.org/stable/c/513f820b3f0cf4462e17d84c39ed3948d061a6ea (opens in a new tab)
- git.kernel.org/stable/c/806b7b6edc8446e8b94b706807a7090a14d47b5c (opens in a new tab)
- git.kernel.org/stable/c/cdf19f380e46192e7084be559638aab1f6ed86a2 (opens in a new tab)
- git.kernel.org/stable/c/e62adb157c2eaad9ad4867ec6cd9af5b9a51b1c7 (opens in a new tab)
- ubuntu.com/security/notices/USN-8876-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8878-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8879-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8877-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8875-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8888-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8889-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8887-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8886-1 (opens in a new tab)