PT-2026-51887 · Linux · Linux

Published 2026-06-24 · Updated 2026-06-24 · CVE-2026-52993

Mitre

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.

Related Identifiers

CVE-2026-52993

Affected Products

Linux

References · 9

• https://nvd.nist.gov/vuln/detail/CVE-2026-52993 · Security Note
• https://git.kernel.org/stable/c/d293ca716e7d5dffdaecaf6b9b2f857a33dc3d3a · Note
• https://git.kernel.org/stable/c/d3556656c6daebf8def751c7e71d11dd0a180d24 · Note
• https://git.kernel.org/stable/c/0274f24485fc38032d4093e463dc3ff5c7a667c9 · Note
• https://git.kernel.org/stable/c/29940fff14110ca48c5ccc168d121665b51bb778 · Note
• https://git.kernel.org/stable/c/a438975a6dcdbd70865978c021650d1485586f0b · Note
• https://git.kernel.org/stable/c/4d104882bc815d4ec666ace9155f5f52715879a6 · Note
• https://git.kernel.org/stable/c/4ee4deadaae7cb2e3d53af0fc889cf92a73413c0 · Note
• https://git.kernel.org/stable/c/1d5e589055880fae229e229e1929e087dbe08cf3 · Note