CVE-2026-63945: Linux kernel · Bluetooth: ISO: serialize iso_sock_clear_timer with socket lock
Source GCVE Database
Not known to be exploited · CVSS 7.8 High · fixed in d9cbf7144ec589a3f0cc91f74a1a1af2d2b14afa : patch Linux kernel soon.
Data as of 26 Oct 2026, 13:47 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 2% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in d9cbf7144ec589a3f0cc91f74a1a1af2d2b14afa, bc08c15746f25f41dd0508b25780d1e84acbb2ef, 996c2104d0726a8fe584f85b3d6327197374a348 +3
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 19 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 |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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AI-suggested
The vulnerability was resolved by serializing iso_sock_clear_timer() with the socket lock in the Linux kernel source code. Users should apply the official Linux kernel updates once available to address this issue.
Description
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: ISO: serialize iso_sock_clear_timer with socket lock iso_sock_close() calls iso_sock_clear_timer() before acquiring lock_sock(sk). iso_sock_clear_timer() reads iso_pi(sk)->conn twice without the socket lock held: if (!iso_pi(sk)->conn) return; cancel_delayed_work(&iso_pi(sk)->conn->timeout_work); Concurrently, iso_conn_del() executes under lock_sock(sk) and calls iso_chan_del(), which sets iso_pi(sk)->conn to NULL and may result in the final reference to the connection being dropped: CPU0 CPU1 ---- ---- iso_sock_clear_timer() if (conn != NULL) ... lock_sock(sk) iso_chan_del() iso_pi(sk)->conn = NULL cancel_delayed_work(conn) /* NULL deref or UAF */ iso_pi(sk)->conn is not stable across the unlock window, causing a NULL pointer dereference or use-after-free. Serialize iso_sock_clear_timer() with the socket lock by moving it inside lock_sock()/release_sock(), matching the pattern used in iso_conn_del() and all other call sites.
References
- nvd.nist.gov/vuln/detail/CVE-2026-63945 (opens in a new tab)
- git.kernel.org/stable/c/35f68f36d9883d56dec21cf85f7556d4657fc393 (opens in a new tab)
- git.kernel.org/stable/c/4b5f8e608749b7e8fa386c6e4301cf9272595859 (opens in a new tab)
- git.kernel.org/stable/c/51cb9dcfdf9a1bccf312ab2ae4b62db629f7dcd5 (opens in a new tab)
- git.kernel.org/stable/c/996c2104d0726a8fe584f85b3d6327197374a348 (opens in a new tab)
- git.kernel.org/stable/c/bc08c15746f25f41dd0508b25780d1e84acbb2ef (opens in a new tab)
- git.kernel.org/stable/c/d9cbf7144ec589a3f0cc91f74a1a1af2d2b14afa (opens in a new tab)