CVE-2026-52993
Last modified
CVE-2026-52993 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. 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. EPSS estimates a 0.37% chance of exploitation in the next 30 days.
Description
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.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux Kernel | >= 4.15, < 5.10.258 |
| Linux | Linux Kernel | >= 5.11, < 5.15.209 |
| Linux | Linux Kernel | >= 5.16, < 6.1.175 |
| Linux | Linux Kernel | >= 6.2, < 6.6.141 |
| Linux | Linux Kernel | >= 6.7, < 6.12.91 |
| Linux | Linux Kernel | >= 6.13, < 6.18.33 |
| Linux | Linux Kernel | >= 6.19, < 7.0.10 |
References
- https://access.redhat.com/security/cve/CVE-2026-52993Third Party Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=2492437Third Party Advisory
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-52993.jsonThird Party Advisory
Timeline
- Published
- Last Modified
- Status
- Modified
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How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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