CVE-2026-97975Bluetooth: hci_sysfs: Fix NULL pointer dereference in device_del()
- —Not scoredno CVSS score yet
- 0.17%Exploitation in 30 daysEPSS · top 94% 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: hci_sysfs: Fix NULL pointer dereference in device_del() A NULL pointer dereference in klist_put() occurs when a child device (such as a BNEP network device in bnep_session) is concurrently being unregistered while hci_conn_del_sysfs() reparents child devices. This is caused by a race condition between hci_conn_del_sysfs() and concurrent child device unregistration (e.g. bnep_session calling unregister_netdev()). During device unregistration, device_del() snapshots a non-NULL parent pointer. Concurrently, hci_conn_del_sysfs() finds the child device using device_find_any_child() and calls device_move() to reparent it to NULL, which removes the node from its parent's klist and clears knode_parent. Subsequently, device_del() calls klist_del(&dev->p->knode_parent) using the stale parent snapshot, causing klist_put() to dereference knode_klist(n)->put on an already removed node, resulting in a NULL pointer dereference. This race was introduced by commit 27aabf27fd01 ("Bluetooth: fix use-after-free in device_for_each_child()"), which replaced device_find_child(..., __match_tty) with device_find_any_child() in hci_conn_del_sysfs(). That change was intended to avoid a use-after-free where conn->dev outlived its parent hdev->dev when child devices held references to conn->dev, because conn->dev only held a reference to hdev->dev while registered in sysfs. Fix the issue properly by taking an explicit reference to the parent device with get_device(&hdev->dev) in hci_conn_init_sysfs() and dropping it with put_device(parent) in bt_link_release() when the conn device is freed. This ensures that hdev->dev remains valid for the entire lifecycle of conn->dev, resolving the underlying use-after-free. With the parent reference held properly, restore the __match_tty filter in hci_conn_del_sysfs() so that device_move() is only invoked on persistent RFCOMM TTY devices as originally intended, eliminating the race condition with unregistering network devices.
Timeline
ID reserved
By Linux
Published
- 26 days later
· 26 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
No CVSS score yet: neither the CNA, CISA nor NVD has scored this CVE. NVD status: Received.
- EPSS (exploitation in 30 days)
- 0.17% · top 94% of all CVEs (13 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Not scored.
Affected products
- affected de5a44f351ca7efd9add9851b218f5353e2224b7 – < 55b76500546e5f2e7fdd7ae7283530b620de6e61
- affected 7b277bd569bb6a2777f0014f84b4344f444fd49d – < 66cc55b69928b742d24b4c5b66d195ae96900e48
- affected 27aabf27fd014ae037cc179c61b0bee7cff55b3d – < eeabdb25c3209569367e99a85ca9a503b64a646d
- affected 27aabf27fd014ae037cc179c61b0bee7cff55b3d – < 9e9ece97b8e716890793de261574b8efef7d8702
- affected 27aabf27fd014ae037cc179c61b0bee7cff55b3d – < 9b851b09b392da68bd715601f10a5adb2d8d19b8
- affected 6894717a1ea363c5a27010ba604f957c309d282d
- affected fb91ce37dc9a37ea23cf32b6d7b667004e93d4c5
- affected a9584c897d1cba6265c78010bbb45ca5722c88bc
- affected 0f67ca2a80acf8b207240405b7f72d660665d3df
- affected 91e2a2e4d1336333804cd31162984f01ad8cc70f
- affected 6.6.64 – < 6.6.160
- affected 6.12.2 – < 6.12.114
- affected 5.4.297 – < 5.5
- affected 5.10.231 – < 5.11
- affected 5.15.174 – < 5.16
- affected 6.1.120 – < 6.2
- affected 6.11.11 – < 6.12
- affected 6.13
- unaffected < 6.13
- unaffected 6.6.160 – ≤ 6.6.*
- unaffected 6.12.114 – ≤ 6.12.*
- unaffected 6.18.53 – ≤ 6.18.*
- unaffected 7.2.7 – ≤ 7.2.*
- unaffected 7.3 – ≤ *
References
References5
- https://git.kernel.org/stable/c/55b76500546e5f2e7fdd7ae7283530b620de6e61 (opens in a new tab)
- https://git.kernel.org/stable/c/66cc55b69928b742d24b4c5b66d195ae96900e48 (opens in a new tab)
- https://git.kernel.org/stable/c/eeabdb25c3209569367e99a85ca9a503b64a646d (opens in a new tab)
- https://git.kernel.org/stable/c/9e9ece97b8e716890793de261574b8efef7d8702 (opens in a new tab)
- https://git.kernel.org/stable/c/9b851b09b392da68bd715601f10a5adb2d8d19b8 (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-2026-86629 (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)
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[](https://cveledger.app/cve/CVE-2026-97975)Record last updated .