CVE-2026-23461Bluetooth: L2CAP: Fix use-after-free in l2cap_unregister_user
- 8.8HighCVSS base score
- 0.24%Exploitation in 30 daysEPSS · top 85% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: Fix use-after-free in l2cap_unregister_user After commit ab4eedb790ca ("Bluetooth: L2CAP: Fix corrupted list in hci_chan_del"), l2cap_conn_del() uses conn->lock to protect access to conn->users. However, l2cap_register_user() and l2cap_unregister_user() don't use conn->lock, creating a race condition where these functions can access conn->users and conn->hchan concurrently with l2cap_conn_del(). This can lead to use-after-free and list corruption bugs, as reported by syzbot. Fix this by changing l2cap_register_user() and l2cap_unregister_user() to use conn->lock instead of hci_dev_lock(), ensuring consistent locking for the l2cap_conn structure.
Timeline
ID reserved
By Linux
- 3 months later
· 3 months later
Published
- 7 months later
· 7 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| LinuxCNA (assigner) | 3.1 | High8.8 | CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Modified | 3.1 | High8.8 | CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.24% · top 85% of all CVEs (13 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.8.
Affected products
- affected efc30877bd4bc85fefe98d80af60fafc86e5775e – < 11a87dd5df428a4b79a84d2790cac7f3c73f1f0d
- affected f87271d21dd4ee83857ca11b94e7b4952749bbae – < c22a5e659959eb77c2fbb58a5adfaf3c3dab7abf
- affected ab4eedb790cae44313759b50fe47da285e2519d5 – < da3000cbe4851458a22be38bb18c0689c39fdd5f
- affected ab4eedb790cae44313759b50fe47da285e2519d5 – < 71030f3b3015a412133a805ff47970cdcf30c2b8
- affected ab4eedb790cae44313759b50fe47da285e2519d5 – < 752a6c9596dd25efd6978a73ff21f3b592668f4a
- affected 18ab6b6078fa8191ca30a3065d57bf35d5635761
- affected 6.6.84 – < 6.6.130
- affected 6.12.20 – < 6.12.78
- affected 6.13.8 – < 6.14
- affected 6.14
- unaffected < 6.14
- unaffected 6.6.130 – ≤ 6.6.*
- unaffected 6.12.78 – ≤ 6.12.*
- unaffected 6.18.20 – ≤ 6.18.*
- unaffected 6.19.10 – ≤ 6.19.*
- unaffected 7.0 – ≤ *
References
References5
- https://git.kernel.org/stable/c/11a87dd5df428a4b79a84d2790cac7f3c73f1f0d (opens in a new tab)
- https://git.kernel.org/stable/c/c22a5e659959eb77c2fbb58a5adfaf3c3dab7abf (opens in a new tab)
- https://git.kernel.org/stable/c/da3000cbe4851458a22be38bb18c0689c39fdd5f (opens in a new tab)
- https://git.kernel.org/stable/c/71030f3b3015a412133a805ff47970cdcf30c2b8 (opens in a new tab)
- https://git.kernel.org/stable/c/752a6c9596dd25efd6978a73ff21f3b592668f4a (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-18722 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-23461)Record last updated .