CVE-2026-98799

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

bpf: Skip detached progs in trampoline images that are still in use

bpf_tramp_image_put() makes sure a trampoline image is not freed while

a task may still be running in it, but nothing similar is done for the

progs called by that image. Detach drops the last prog reference right

away and the prog is freed after grace periods, on the basis that a

task still in the traced function skips the fexit progs once the nop at

ip_after_call is patched to a jump.

That leaves out a task sleeping in a sleepable prog that runs before

the detached one, which no grace period waits for:

CPU 0 CPU 1

in image I, sleeping in prog S

detach P from I's trampoline

-> new image, bpf_tramp_image_put(I)

bpf_prog_put(P), last ref

grace periods, P freed

back

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References