USN-8388-1: Linux kernel vulnerabilities

It was discovered that the Linux kernel did not properly handle shared page
fragments during socket buffer operations, collectively known as Dirty
Frag. A logic flaw existed in the XFRM ESP-in-TCP subsystem and in the
RxRPC networking subsystem when processing paged fragments. A local
attacker could use this to escalate privileges, or possibly escape a
container. (CVE-2026-43284, CVE-2026-43500)

It was discovered that a logic flaw existed in the XFRM ESP-in-TCP
subsystem in the Linux kernel when handling socket buffer fragments. This
flaw is known as Fragnesia. A local attacker could use this to escalate
privileges, or possibly escape a container. (CVE-2026-43503,
CVE-2026-46300)

Qualys discovered that a race condition existed in the ptrace subsystem of
the Linux kernel when privileged processes are exiting. An unprivileged
local attacker could use this issue to expose sensitive information.
(CVE-2026-46333)

Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- RDS protocol;
(CVE-2026-43494)