« List of all CVEs

CVE-2026-53095

bpf: Fix abuse of kprobe_write_ctx via freplace

Published: 6/24/2026 Last updated: 6/24/2026 Reserved: 6/9/2026

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix abuse of kprobe_write_ctx via freplace uprobe programs are allowed to modify struct pt_regs. Since the actual program type of uprobe is KPROBE, it can be abused to modify struct pt_regs via kprobe+freplace when the kprobe attaches to kernel functions. For example, SEC("?kprobe") int kprobe(struct pt_regs *regs) { return 0; } SEC("?freplace") int freplace_kprobe(struct pt_regs *regs) { regs->di = 0; return 0; } freplace_kprobe prog will attach to kprobe prog. kprobe prog will attach to a kernel function. Without this patch, when the kernel function runs, its first arg will always be set as 0 via the freplace_kprobe prog. To fix the abuse of kprobe_write_ctx=true via kprobe+freplace, disallow attaching freplace programs on kprobe programs with different kprobe_write_ctx values.

CNA assigner: Linux (416baaa9-dc9f-4396-8d5f-8c081fb06d67) Requested by: n/a

Opam packages affected (29)

albatross cdrom conf-bpftool conf-libbpf conf-linux-libc-dev core core_unix hvsock mirage-block-unix mm ocaml-probes ortools_solvers orun rawlink rawlink-eio rawlink-lwt restricted shell solo5 solo5-bindings-hvt solo5-bindings-spt solo5-cross-aarch64 solo5-kernel-ukvm tracy-client tuntap uring vhd-format vhd-format-lwt xapi-stdext-unix

Products affected (2)

Product Vendor Version
Linux Linux before 1.71
Linux Linux before 1.71

References (3)