CVE-2026-64575

Status: UPDATED  |  Advisory ID: CVE-2026-64575

Key Details

Affected Products, Subsystems & Sectors

What to Know

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

bpf: tcp: fix double sock release on batch realloc

bpf_iter_tcp_batch() releases the current batch via

bpf_iter_tcp_put_batch(), which drops the socket refs and rewrites

each slot with the socket cookie, then grows the batch. cur_sk/end_sk

are kept for bpf_iter_tcp_resume(), but on realloc failure the function

returns ERR_PTR() before resume runs, leaving cur_sk < end_sk over

slots that now hold cookies rather than sock pointers.

bpf_iter_tcp_seq_stop() then calls bpf_iter_tcp_put_batch() again and

dereferences a cookie as a struct sock.

Empty the batch on the failure path so stop() does not release it

again. The sockets were already freed by the first

bpf_iter_tcp_put_batch(), so nothing leaks, and a later read() rescans

the bucket from the start instead of skipping it. The sibling

GFP_NOWAIT failure path still holds real socket references and is left

for stop() to release.

BUG: KASAN: null-ptr-deref in __sock_gen_cookie

Read of size 8 at addr 0000000000000059 by task exploit

...

__sock_gen_cookie (net/core/sock_diag.c:28)

bpf_iter_tcp_put_batch (net/ipv4/tcp_ipv4.c:2918)

bpf_iter_tcp_seq_stop (net/ipv4/tcp_ipv4.c:3270)

bpf_seq_read (kernel/bpf/bpf_iter.c:205)

vfs_read (fs/read_write.c:572)

ksys_read (fs/read_write.c:716)

do_syscall_64

entry_SYSCALL_64_after_hwframe

Kernel panic - not syncing: Fatal exception (NVD)

What to Do

Monitor Linux's web page for any future patch releases.

References