VulnerabilityPublished 19 Jul 2026

CVE-2026-63871: Linux kernel · Bluetooth: ISO: Fix data-race on iso_pi fields in hci_get_route calls

Source GCVE Database

Not known to be exploited.

Data as of 26 Oct 2026, 14:05 UTC

Severity

Medium

Rated by Threat Radar · No CVSS score from NVD or the CNA

EPSS: 0.1% chance of exploitation in 30 days – higher than 5% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

Exploitation 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.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

ghsa-5243-p4qj-j66v

What to do

AI-suggested

A fix is available and has been applied in the Linux kernel to snapshot iso_pi fields under lock_sock() before use. Users should update to the fixed kernel version once available. Patch status is not explicitly confirmed in the provided data; check the official Linux kernel advisories or vendor updates for the exact fixed versions and apply updates accordingly.

Description

A data-race vulnerability in the Linux kernel Bluetooth ISO subsystem was fixed. The issue involved concurrent access to iso_pi fields in hci_get_route calls without proper locking, leading to potential data races detected by KCSAN. The flaw affected functions iso_connect_bis(), iso_connect_cis(), iso_listen_bis(), and iso_conn_big_sync(). The fix involves snapshotting the relevant fields under lock_sock() before use to prevent concurrent modification.

References

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