Cyber Resilience

CVE-2026-52993

Critical

Published: 24 June 2026

Published
24 June 2026
Modified
30 June 2026
KEV Added
Patch
CVSS Score v3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0035 27.1th percentile
Risk Priority 70 floored blend · peak EPSS

Summary

CVE-2026-52993 is a critical-severity Release of Invalid Pointer or Reference (CWE-763) vulnerability in Kernel (inferred from references). Its CVSS base score is 9.8 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 27.1th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

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…

more

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.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
Why these techniques?

Double-free memory corruption in kernel TIPC skb handling directly enables local/remote kernel exploitation for privilege escalation.

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

Affected Assets

Kernel
inferred from references and description; NVD did not file a CPE for this CVE

Mitigating Controls

No mitigating controls mapped yet. The per-CVE control annotator has not reached this CVE.

References