Kernel use-after-free via unlocked SCO socket
Published Sep 16, 2026 · Updated Sep 16, 2026
Use-after-free in Linux 5.15 and affected commits allows attackers to access a freed Bluetooth SCO socket during connection setup. The sco_conn_ready function dereferences conn->sk and a listening parent socket without holding a reference or the required lock while another task can close and free either socket. Triggering the race requires concurrent SCO connection readiness and socket closure; the disclosure establishes a kernel memory-safety violation but does not document code execution or a reliable crash.
Summary
What happened
Use-after-free in Linux 5.15 and affected commits allows attackers to access a freed Bluetooth SCO socket during connection setup. The sco_conn_ready function dereferences conn->sk and a listening parent socket without holding a reference or the required lock while another task can close and free either socket. Triggering the race requires concurrent SCO connection readiness and socket closure; the disclosure establishes a kernel memory-safety violation but does not document code execution or a reliable crash.
The record
- CVE
- CVE-2026-89774
- Published
- Sep 16, 2026
- Updated
- Sep 16, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- Unavailable
- Attack vector
- local
- Privileges
- Unavailable
Timeline
How it unfolded
- Sep 16, 2026CVE publishedPublication date reported by the CVE source.
- Sep 16, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=27c24fda62b601d6f9ca5e992502578c4310876f <4e37f6452d586b95c346a9abdd2fb80b67794f39
- Affected versionversion=27c24fda62b601d6f9ca5e992502578c4310876f <50aae396dc30377bec8e3b181b8346f8fd38f7d8
- Affected versionversion=27c24fda62b601d6f9ca5e992502578c4310876f <6e3840578aaad1a296aab1eaaa89ea3b7d5cbae1
- Affected versionversion=27c24fda62b601d6f9ca5e992502578c4310876f <7199c78c3a3e399a4dc439d845826793880ccedc
- Affected versionversion=27c24fda62b601d6f9ca5e992502578c4310876f <73cb063f5ec6ca51eb1e246c6d332563002ac277
- Affected versionversion=27c24fda62b601d6f9ca5e992502578c4310876f <d141d9b769bcd1b747898528c5023270cda040f2
- Affected versionversion=5.15
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
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Weakness, pattern, technique
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Public exploit references
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Technologies
Your stack
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Your stack
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