CVE-2026-52993CWE-415CWE-763

CVE-2026-52993

Critical · published June 24, 2026

CVSS v3.1
9.8
EPSS
0%
Percentile
33.5
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
9.8 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.00404 · 33.5th percentile
Weaknesses
CWE-415 · Double Free; CWE-763 · Release of Invalid Pointer or Reference
Published
2026-06-24T21:17Z
Affected products (7)
ProductVersionsFixed in
linux/linux_kernel≥ 4.15, < 5.10.2585.10.258
linux/linux_kernel≥ 5.11, < 5.15.2095.15.209
linux/linux_kernel≥ 5.16, < 6.1.1756.1.175
linux/linux_kernel≥ 6.2, < 6.6.1416.6.141
linux/linux_kernel≥ 6.7, < 6.12.916.12.91
linux/linux_kernel≥ 6.13, < 6.18.336.18.33
linux/linux_kernel≥ 6.19, < 7.0.107.0.10
References (15)
https://git.kernel.org/stable/c/0274f24485fc38032d4093e463dc3ff5c7a667c9 · 416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/1d5e589055880fae229e229e1929e087dbe08cf3 · 416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/29940fff14110ca48c5ccc168d121665b51bb778 · 416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/4d104882bc815d4ec666ace9155f5f52715879a6 · 416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/4ee4deadaae7cb2e3d53af0fc889cf92a73413c0 · 416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/a438975a6dcdbd70865978c021650d1485586f0b · 416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/d293ca716e7d5dffdaecaf6b9b2f857a33dc3d3a · 416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/d3556656c6daebf8def751c7e71d11dd0a180d24 · 416baaa9-dc9f-4396-8d5f-8c081fb06d67https://access.redhat.com/errata/RHSA-2026:45115 · 0b0ca135-0b70-47e7-9f44-1890c2a1c46chttps://access.redhat.com/errata/RHSA-2026:45116 · 0b0ca135-0b70-47e7-9f44-1890c2a1c46chttps://access.redhat.com/errata/RHSA-2026:47017 · 0b0ca135-0b70-47e7-9f44-1890c2a1c46chttps://access.redhat.com/errata/RHSA-2026:49212 · 0b0ca135-0b70-47e7-9f44-1890c2a1c46chttps://access.redhat.com/security/cve/CVE-2026-52993 · 0b0ca135-0b70-47e7-9f44-1890c2a1c46chttps://bugzilla.redhat.com/show_bug.cgi?id=2492437 · 0b0ca135-0b70-47e7-9f44-1890c2a1c46chttps://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-52993.json · 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
EPSS history
Timeline
  • 24 JUN 16:29Z
    tipc: fix double-free in tipc_buf_append()
    cvelistv5