CVE-2026-64548 bpf, sockmap: reject overflowing copy + len in bpf_msg_push_data()
An integer overflow in the Linux kernel's BPF sockmap allows attackers to trigger out-of-bounds memory writes, potentially leading to code execution or system crashes.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-64548?
CVE-2026-64548 is a high-severity vulnerability in Linux, published on 27 Jul 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
bpf, sockmap: reject overflowing copy + len in bpf_msg_push_data()
When the scatterlist ring is full or nearly full, bpf_msg_push_data() enters a copy fallback path and computes copy + len for the page allocation size. Since len comes from BPF with arg3_type = ARG_ANYTHING and both are u32, a crafted len can wrap the sum to a small value, causing an undersized allocation followed by an out-of-bounds memcpy.
BUG: unable to handle page fault for address: ffffed104089a402 Oops: Oops: 0000 [#1] SMP KASAN NOPTI Call Trace: __asan_memcpy (mm/kasan/shadow.c:105) bpf_msg_push_data (net/core/filter.c:2852 net/core/filter.c:2788) bpf_prog_9ed8b5711920a7d7+0x2e/0x36 sk_psock_msg_verdict (net/core/skmsg.c:934) tcp_bpf_sendmsg (net/ipv4/tcp_bpf.c:421 net/ipv4/tcp_bpf.c:584) __sys_sendto (net/socket.c:2206) do_syscall_64 (arch/x86/entry/syscall_64.c:94) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
Add an overflow check before the allocation.
Weakness: CWE-190
Which versions are affected by CVE-2026-64548?
How do I fix CVE-2026-64548?
Apply the vendor's patch.
Is CVE-2026-64548 being exploited?
There is no known exploitation of CVE-2026-64548 in the wild and no public exploit code.
Sources
Also known as AZL-94053, BELL-CVE-2026-64548, DEBIAN-CVE-2026-64548, GHSA-v3w7-wgcw-wjf2, ROOT-OS-DEBIAN-12-CVE-2026-64548, UBUNTU-CVE-2026-64548.