CVE-2026-23419
MediumIn the Linux kernel, the following vulnerability has been resolved: net/rds: Fix circular locking dependency in rds_tcp_tune syzbot reported a circular locking dependency in rds_tcp_tune() where sk_net_refcnt_upgrade() is called while holding the socket lock: ====================================================== WARNING: possible circular locking dependency detected ====================================================== kworker/u10:8/15040 is trying to acquire lock: ffffffff8e9aaf80 (fs_reclaim){+.+.}-{0:0}, at: __kmalloc_cache_noprof+0x4b/0x6f0 but task is already holding lock: ffff88805a3c1ce0 (k-sk_lock-AF_INET6){+.+.}-{0:0}, at: rds_tcp_tune+0xd7/0x930 The issue occurs because sk_net_refcnt_upgrade() performs memory allocation (via get_net_track() -> ref_tracker_alloc()) while the socket lock is held, creating a circular dependency with fs_reclaim. Fix this by moving sk_net_refcnt_upgrade() outside the socket lock critical section. This is safe because the fields modified by the sk_net_refcnt_upgrade() call (sk_net_refcnt, ns_tracker) are not accessed by any concurrent code path at this point. v2: - Corrected fixes tag - check patch line wrap nits - ai commentary nits
CVSS 3.1 score
5.5
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Weakness type
CWE-667CVE-2026-23419 is a Improper Locking vulnerability
What is Improper Locking?
The product does not properly acquire or release a lock, which can lead to unexpected behaviour. Learn more on MITRE CWE
Affected versions
Linux kernel versions
5.17.7,
5.18
and later are affected. Fixed in
6.6.130,
6.12.77,
6.18.17,
6.19.7,
7.0
and their respective stable series.
References
The following references provide additional information about CVE-2026-23419 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.
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PatchKernel patch commithttps://git.kernel.org/stable/c/026bbaeeab9e04534ee58882b6447300629b42f6
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PatchKernel patch commithttps://git.kernel.org/stable/c/6a877ececd6daa002a9a0002cd0fbca6592a9244
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PatchKernel patch commithttps://git.kernel.org/stable/c/6ce948fa54599f369ff7fe8b793a6aae4b0762b2
Frequently asked questions
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What is CVE-2026-23419?
CVE-2026-23419 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 , classified as an Improper Locking flaw (CWE-667) . It affects Linux kernel versions from 5.17.7 onward and has been patched in 6.6.130, 6.12.77, 6.18.17 and others. CVE-2026-23419 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
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What is the CVSS score for CVE-2026-23419?
CVE-2026-23419 has a CVSS score of 5.5 out of 10, rated Medium severity (CVSS 3.1). The vector string is
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H. -
Is there a patch available for CVE-2026-23419?
Yes — CVE-2026-23419 has been patched. Fixed versions include 6.6.130, 6.12.77, 6.18.17 and others. If you are running Linux kernel 5.17.7 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2026-23419 actively exploited?
No — CVE-2026-23419 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
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What is Improper Locking (CWE-667)?
The product does not properly acquire or release a lock, which can lead to unexpected behaviour. View CWE-667 on MITRE CWE →