HIGH · 8.8

CVE-2026-89774

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: SCO: hold sk properly in sco_conn_ready sk deref in sco_conn_ready must be done either under conn->lock, or holding a r...

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: SCO: hold sk properly in sco_conn_ready sk deref in sco_conn_ready must be done either under conn->lock, or holding a refcount, to avoid concurrent close. conn->sk and parent sk is currently accessed without either, and without checking parent->sk_state: [Task 1] [Task 2] sco_sock_release sco_conn_ready sk = conn->sk lock_sock(sk) conn->sk = NULL lock_sock(sk) release_sock(sk) sco_sock_kill(sk) UAF on sk deref and similarly for access to sco_get_sock_listen() return value. Fix possible UAF by holding sk refcount in sco_conn_ready() and making sco_get_sock_listen() increase refcount. Also recheck after lock_sock that the socket is still valid. Adjust conn->sk locking so it's protected also by lock_sock() of the associated socket if any.

CVSS Score

8.8

HIGH

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack Vector
ADJACENT_NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH

References

FAQ

What is CVE-2026-89774?

CVE-2026-89774 is a vulnerability with a CVSS score of 8.8 (HIGH). In the Linux kernel, the following vulnerability has been resolved: Bluetooth: SCO: hold sk properly in sco_conn_ready sk deref in sco_conn_ready must be done either under conn->lock, or holding a r...

How severe is CVE-2026-89774?

CVE-2026-89774 has been rated HIGH with a CVSS base score of 8.8/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-89774?

Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.