CVE-2026-52993

Critical

In the Linux kernel, the following vulnerability has been resolved: tipc: fix double-free in tipc_buf_append() tipc_msg_validate() can potentially reallocate the skb it is validating, freeing the old one. In tipc_buf_append(), it was being called with a pointer to a local variable which was a copy of the caller's skb pointer. If the skb was reallocated and validation subsequently failed, the error handling path would free the original skb pointer, which had already been freed, leading to double-free. Fix this by checking if head now points to a newly allocated reassembled skb. If it does, reassign *headbuf for later freeing operations.

Package Linux Kernel
Published 2026-06-24
Last modified 2026-08-03
CVSS version 3.1
Patch available
Yes

CVSS 3.1 score

9.8

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

Weakness type

CWE-415

CVE-2026-52993 is classified as CWE-415

See CWE-415 on MITRE CWE for full details on this weakness type.

Affected versions

Linux kernel versions 4.15 and later are affected. Fixed in 5.10.258, 5.15.209, 6.1.175, 6.6.141, 6.12.91, 6.18.33, 7.0.10, 7.1 and their respective stable series.

Affected from
≥ 4.15
Fixed in
✓ 5.10.258 5.10.x ✓ 5.15.209 5.15.x ✓ 6.1.175 6.1.x ✓ 6.6.141 6.6.x ✓ 6.12.91 6.12.x ✓ 6.18.33 6.18.x ✓ 7.0.10 7.0.x ✓ 7.1

References

15 total
Showing 5 of 15 references View all on NVD

Frequently asked questions

  • What is CVE-2026-52993?

    CVE-2026-52993 is a Critical severity Linux kernel vulnerability with a CVSS score of 9.8 out of 10 . It affects Linux kernel versions from 4.15 onward and has been patched in 5.10.258, 5.15.209, 6.1.175 and others. CVE-2026-52993 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

  • What is the CVSS score for CVE-2026-52993?

    CVE-2026-52993 has a CVSS score of 9.8 out of 10, rated Critical severity (CVSS 3.1). The vector string is CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H .

  • Is there a patch available for CVE-2026-52993?

    Yes. CVE-2026-52993 has been patched. Fixed versions include 5.10.258, 5.15.209, 6.1.175 and others. If you are running Linux kernel 4.15 or later up to the fix versions, apply the relevant patch for your kernel branch.

  • Is CVE-2026-52993 actively exploited?

    No. CVE-2026-52993 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

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