CVE-2026-52993
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.
At a glance
- Exploitability
- Can be exploited over the network without logging in. High risk of data exposure, data tampering, service disruption.
- Exploit odds
- 0.4% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.4% in the next 30 days (EPSS).
- Severity: 9.8 CRITICAL (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.4% · EPSS, next 30 days
- Weakness
- CWE-415
- Record status
- Modified
Affected
- Linux Kernel < 5.10.258
- Linux Kernel < 5.15.209
- Linux Kernel < 6.1.175
- Linux Kernel < 6.6.141
- Linux Kernel < 6.12.91
- Linux Kernel < 6.18.33
- Linux Kernel < 7.0.10
Attack profile CVSS 3.1 · 9.8
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-52993.md and follow it. Check whether this project is affected by CVE-2026-52993. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://git.kernel.org/stable/c/0274f24485fc38032d4093e463dc3ff5c7a667c9
- https://git.kernel.org/stable/c/1d5e589055880fae229e229e1929e087dbe08cf3
- https://git.kernel.org/stable/c/29940fff14110ca48c5ccc168d121665b51bb778
- https://git.kernel.org/stable/c/4d104882bc815d4ec666ace9155f5f52715879a6
- https://git.kernel.org/stable/c/4ee4deadaae7cb2e3d53af0fc889cf92a73413c0
- https://git.kernel.org/stable/c/a438975a6dcdbd70865978c021650d1485586f0b
- https://git.kernel.org/stable/c/d293ca716e7d5dffdaecaf6b9b2f857a33dc3d3a
- https://git.kernel.org/stable/c/d3556656c6daebf8def751c7e71d11dd0a180d24
References
- https://git.kernel.org/stable/c/0274f24485fc38032d4093e463dc3ff5c7a667c9
- https://git.kernel.org/stable/c/1d5e589055880fae229e229e1929e087dbe08cf3
- https://git.kernel.org/stable/c/29940fff14110ca48c5ccc168d121665b51bb778
- https://git.kernel.org/stable/c/4d104882bc815d4ec666ace9155f5f52715879a6
- https://git.kernel.org/stable/c/4ee4deadaae7cb2e3d53af0fc889cf92a73413c0
- https://git.kernel.org/stable/c/a438975a6dcdbd70865978c021650d1485586f0b
- https://git.kernel.org/stable/c/d293ca716e7d5dffdaecaf6b9b2f857a33dc3d3a
- https://git.kernel.org/stable/c/d3556656c6daebf8def751c7e71d11dd0a180d24
- https://access.redhat.com/errata/RHSA-2026:45115
- https://access.redhat.com/errata/RHSA-2026:45116
- https://access.redhat.com/errata/RHSA-2026:47017
- https://access.redhat.com/errata/RHSA-2026:49212
- https://access.redhat.com/security/cve/CVE-2026-52993
- https://bugzilla.redhat.com/show_bug.cgi?id=2492437
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-52993.json