CVE-2026-53357: Linux kernel · Bluetooth: fix UAF in l2cap_sock_cleanup_listen() vs l2cap_conn_del()
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 8.0 High · fixed in 5.15.0-1117.124~20.04.1 : patch Linux kernel soon.
Data as of 26 Oct 2026, 13:47 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 26% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- 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 +67
CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 2 Jul 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 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.
AI-suggested
A patch is available and has been released by Ubuntu as part of their security updates. Users should apply the provided kernel updates promptly and reboot affected systems to remediate this vulnerability. No additional mitigation is required beyond applying the official fixes.
Description
A use-after-free vulnerability (CVE-2026-53357) in the Linux kernel's Bluetooth subsystem was resolved. The flaw occurs due to improper handling of socket cleanup in the l2cap_sock_cleanup_listen() function concurrent with connection deletion, leading to use-after-free conditions. This vulnerability has a high severity with a CVSS score of 8.0. Multiple Linux kernel versions prior to 7.0.0-28.28 and related builds are affected. Ubuntu has released patches addressing this and other kernel vulnerabilities, requiring system updates and reboots.
References
- ubuntu.com/security/CVE-2026-53357 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-53357 (opens in a new tab)
- git.kernel.org/linus/ab1513597c6cf17cd1ad2a21e3b045421b48e022 (opens in a new tab)
- git.kernel.org/stable/c/407217734835d21d4e0105ebf347860dc1806f88 (opens in a new tab)
- git.kernel.org/stable/c/5d86d2f1b4d9a508c441d3e45277ae1a73cfed57 (opens in a new tab)
- git.kernel.org/stable/c/751de6ec671fe75ad9cf65a0638d2a06b6a5984d (opens in a new tab)
- git.kernel.org/stable/c/7eebd4c2c86f573af87ff165d08a83432eb0b919 (opens in a new tab)
- git.kernel.org/stable/c/87c543e2f78d0871f271df92dab98901bbd5b6f5 (opens in a new tab)
- git.kernel.org/stable/c/a5ca86a6097a8b030ca3226cd300b17ed330f966 (opens in a new tab)
- git.kernel.org/stable/c/ab1513597c6cf17cd1ad2a21e3b045421b48e022 (opens in a new tab)
- git.kernel.org/stable/c/added1213395071470a900cc845a042fb51882a6 (opens in a new tab)
- ubuntu.com/security/notices/USN-8566-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8568-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8569-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8593-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8603-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8618-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8663-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8664-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8728-1 (opens in a new tab)