CVE-2026-43019: Linux kernel · Bluetooth: hci_conn: fix potential UAF in set_cig_params_sync
Affects Linux kernelSource CVE Database V5
Not known to be exploited · CVSS 7.8 High · fixed in bad65b4b0a96139f023eadc28a33125963208449 : patch Linux kernel soon.
Data as of 26 Oct 2026, 12:55 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 0% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- CISA SSVC
- Exploitation
- No evidence of active exploitation and no public proof of concept
- Automatable
- Attackers cannot reliably automate steps 1–4 of the kill chain
- Technical impact
- Total control over the software or total information disclosure
CISA SSVC assessment, 2026-10-16.
- Patch
- Available – fixed in bad65b4b0a96139f023eadc28a33125963208449, a2639a7f0f5bf7d73f337f8f077c19415c62ed2c, 7502c1cf303b69f71d085f5ff7251b0e1b0f09df +4
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 1 May 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
|
| LinuxLinux | Affected
| Fixed in– |
Description
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_conn: fix potential UAF in set_cig_params_sync hci_conn lookup and field access must be covered by hdev lock in set_cig_params_sync, otherwise it's possible it is freed concurrently. Take hdev lock to prevent hci_conn from being deleted or modified concurrently. Just RCU lock is not suitable here, as we also want to avoid "tearing" in the configuration.
References
- git.kernel.org/stable/c/7502c1cf303b69f71d085f5ff7251b0e1b0f09df (opens in a new tab)
- git.kernel.org/stable/c/66d432e9b45bae7881ffcdb12cd8fd0bf254ef02 (opens in a new tab)
- git.kernel.org/stable/c/7d568fede8eac91161a60b710aa920abe9b0fb9f (opens in a new tab)
- git.kernel.org/stable/c/bad65b4b0a96139f023eadc28a33125963208449 (opens in a new tab)
- git.kernel.org/stable/c/a2639a7f0f5bf7d73f337f8f077c19415c62ed2c (opens in a new tab)