Review reviewHigh

CVE-2026-63980

Linux

In the Linux kernel, the following vulnerability has been resolved: net/handshake: Use spin_lock_bh for hn_lock nvmet_tcp_state_change(), a socket callback that runs in BH context, can reach handshake_req_cancel() via nvmet_tcp_schedule_release_queue() and tls_handshake_cancel(). handshake_req_cancel() acquires hn->hn_lock with plain spin_lock(). If a process-context thread on the same CPU holds hn->hn_lock when a softirq invokes the cancel path, the lock attempt deadlocks. This is the only caller that invokes tls_handshake_cancel() from BH context; every other consumer calls it from proces...

CVSS: 7.5
EPSS: -
CISA KEV: Not listed
Published: 2026.07.20

PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV

Exploit probability-

Technical severityCVSS 7.5

Vulnerability overview

Affected product and versions

Product: Linux
Affected versions: >= 675b453e024154dd547921c6e6d5b58747ba7e0e < 06ab5978866fc2221b910347fd3e510ca8e7b1a4, >= 675b453e024154dd547921c6e6d5b58747ba7e0e < 0866569fc36a56f568acd3900d354e3505932e09, >= 675b453e024154dd547921c6e6d5b58747ba7e0e < 91898de9501a047ba67c6b864dcd403e00bdfbf5, >= 675b453e024154dd547921c6e6d5b58747ba7e0e < cc993e0927ec8bd98ea33377ada03295fcda0f24, >= 6.7
Fixed versions: No verified fixed-version field is available yet

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide

1
Identify
Confirm that Linux and an affected version are present.
2
Prioritize
Combine exploitation signals with asset exposure and business criticality.
3
Remediate
Follow the vendor advisory or supported update path and preserve rollback options.
4
Verify
Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE: Not available