CVE-2026-63973

Medium

In the Linux kernel, the following vulnerability has been resolved: net: mana: Add NULL guards in teardown path to prevent panic on attach failure When queue allocation fails partway through, the error cleanup frees and NULLs apc->tx_qp and apc->rxqs. Multiple teardown paths such as mana_remove(), mana_change_mtu() recovery, and internal error handling in mana_alloc_queues() can subsequently call into functions that dereference these pointers without NULL checks: - mana_chn_setxdp() dereferences apc->rxqs[0], causing a NULL pointer dereference panic (CR2: 0000000000000000 at mana_chn_setxdp+0x26). - mana_destroy_vport() iterates apc->rxqs without a NULL check. - mana_fence_rqs() iterates apc->rxqs without a NULL check. - mana_dealloc_queues() iterates apc->tx_qp without a NULL check. Add NULL guards for apc->rxqs in mana_fence_rqs(), mana_destroy_vport(), and before the mana_chn_setxdp() call. Add a NULL guard for apc->tx_qp in mana_dealloc_queues() to skip TX queue draining when TX queues were never allocated or already freed.

Package Linux Kernel
Published 2026-07-19
Last modified 2026-10-02
CVSS version 3.1
Patch available
Yes

CVSS 3.1 score

5.5

out of 10
Medium
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
None
Availability
High
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Weakness type

CWE-476

CVE-2026-63973 is a NULL Pointer Dereference vulnerability

What is NULL Pointer Dereference?

The product dereferences a pointer that it expects to be valid but is NULL, typically causing a crash. Learn more on MITRE CWE

Affected versions

Linux kernel versions 5.13 and later are affected. Fixed in 6.1.176, 6.6.143, 6.12.93, 6.18.35, 7.0.12, 7.1 and their respective stable series.

Affected from
≥ 5.13
Fixed in
✓ 6.1.176 6.1.x ✓ 6.6.143 6.6.x ✓ 6.12.93 6.12.x ✓ 6.18.35 6.18.x ✓ 7.0.12 7.0.x ✓ 7.1

References

6 total
Showing 5 of 6 references View all on NVD

Frequently asked questions

  • What is CVE-2026-63973?

    CVE-2026-63973 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 , classified as a NULL Pointer Dereference flaw (CWE-476) . It affects Linux kernel versions from 5.13 onward and has been patched in 6.1.176, 6.6.143, 6.12.93 and others. CVE-2026-63973 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

  • What is the CVSS score for CVE-2026-63973?

    CVE-2026-63973 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-2026-63973?

    Yes. CVE-2026-63973 has been patched. Fixed versions include 6.1.176, 6.6.143, 6.12.93 and others. If you are running Linux kernel 5.13 or later up to the fix versions, apply the relevant patch for your kernel branch.

  • Is CVE-2026-63973 actively exploited?

    No. CVE-2026-63973 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

Back to
All CVEs
View on
NVD / NIST