CVE-2026-90091Bluetooth: L2CAP: fix race l2cap_sock_cleanup_listen() vs. put_chan
- 8.0HighCVSS base score
- 0.36%Exploitation in 30 daysEPSS · top 70% 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 race l2cap_sock_cleanup_listen() vs. put_chan For L2CAP sockets without owning sk->sk_socket, reading l2cap_pi(sk)->chan may race against concurrent l2cap_sock_kill() -> l2cap_sock_put_chan(). This excludes simultaneous proto_ops callbacks, but access in l2cap_sock_cleanup_listen() has unsafe lockless read. [Task 1] [Task 2 (hdev->workqueue)] l2cap_sock_release(parent) l2cap_disconn_cfm l2cap_sock_cleanup_listen l2cap_conn_del bt_accept_dequeue l2cap_chan_del lock_sock(sk) l2cap_sock_teardown_cb bt_accept_unlink bt_sk(sk)->parent = NULL release_sock(sk) ----------------> lock_sock(sk) parent = /* NULL */ lock_sock(sk) <--------------------- release_sock(sk) sock_set_flag(sk, SOCK_ZAPPED) l2cap_sock_close_cb l2cap_sock_kill(sk) l2cap_sock_put_chan chan = READ l2cap_pi(sk)->chan l2cap_pi(sk)->chan = NULL l2cap_chan_hold_unless_zero l2cap_put_chan(chan) kref_get_unless_zero(&chan->ref) Task 1 may observe NULL which causes null-ptr-deref. Fix the race by taking lock_sock() in l2cap_sock_kill() to synchronize with l2cap_sock_cleanup_listen(). hold_unless_zero() is not needed here, l2cap_pi(sk)->chan owns reference if it is non-NULL. Clarify code comments vs. locking.
Timeline
ID reserved
By Linux
- 6 days later
· 6 days later
Published
- 32 days later
· 32 days 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 | High8.0 | CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Received | 3.1 | High8.0 | CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.36% · top 70% of all CVEs (15 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.0.
Affected products
- affected b39298044e5534612511a2ff5de03ba5f6e7a820 – < 827de6bd2865b22aaabd554540def3b8a33018ab
- affected 8c37e4338c801ebb8cee52436c01c41e009f6e87 – < 7c7ac736b50fa259ed1bdddc18d79523f07c0442
- affected 84e718b6a814edc84159361f9f454a4e92ae91ae – < 4f8c63fe0097c9f6ea34409f82f79b3894903d91
- affected 36da806f7fbaee56ad9e81859deec203f9728700 – < 61d5ddbd524c715b224cbe7e9f01da4e05098b19
- affected 6fef032af0092ed5ccb767239a9ac1bc38c08a40 – < 32a7bc6e93be36b37fe61f351d312d358195bd61
- affected 6fef032af0092ed5ccb767239a9ac1bc38c08a40 – < 66d6ef18548ae6d7dd452b84115fc82c0a73a4ea
- affected 733e76e74e406c1d1ddc7369420dd8a47f48bb8a
- affected 6.1.178 – < 6.1.188
- affected 6.6.145 – < 6.6.157
- affected 6.12.97 – < 6.12.110
- affected 6.18.40 – < 6.18.52
- affected 7.1.5 – < 7.2
- affected 7.2
- unaffected < 7.2
- unaffected 6.1.188 – ≤ 6.1.*
- unaffected 6.6.157 – ≤ 6.6.*
- unaffected 6.12.110 – ≤ 6.12.*
- unaffected 6.18.52 – ≤ 6.18.*
- unaffected 7.2.6 – ≤ 7.2.*
- unaffected 7.3 – ≤ *
References
References6
- https://git.kernel.org/stable/c/827de6bd2865b22aaabd554540def3b8a33018ab (opens in a new tab)
- https://git.kernel.org/stable/c/7c7ac736b50fa259ed1bdddc18d79523f07c0442 (opens in a new tab)
- https://git.kernel.org/stable/c/4f8c63fe0097c9f6ea34409f82f79b3894903d91 (opens in a new tab)
- https://git.kernel.org/stable/c/61d5ddbd524c715b224cbe7e9f01da4e05098b19 (opens in a new tab)
- https://git.kernel.org/stable/c/32a7bc6e93be36b37fe61f351d312d358195bd61 (opens in a new tab)
- https://git.kernel.org/stable/c/66d6ef18548ae6d7dd452b84115fc82c0a73a4ea (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-2026-81952 (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-2026-90091)Record last updated .