CVE-2026-80564 gve: fix NULL dereference due to missing ptp adjfine
A local attacker with low privileges can cause a kernel crash in the gve driver by triggering a NULL pointer dereference via PTP clock adjustment.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-80564?
CVE-2026-80564 is a vulnerability in Linux, published on 26 Aug 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:
gve: fix NULL dereference due to missing ptp adjfine
Fix NULL dereference due to missing implementation of adjfine, which can be triggered from usermode as follows:
sudo ./testptp -d /dev/ptp0 -f 0 [ 551.943697] BUG: kernel NULL pointer dereference, address: 0000000000000000 [...] [ 552.061946] Call Trace: [ 552.064487] <TASK> [ 552.066681] ptp_clock_adjtime+0x1c0/0x2c0 [ 552.070874] ? get_clock_desc+0x6b/0xb0 [ 552.074825] pc_clock_adjtime+0x78/0xc0 [ 552.078755] __do_sys_clock_adjtime+0x85/0x110 [ 552.083293] do_syscall_64+0xea/0x610
Which versions are affected by CVE-2026-80564?
How do I fix CVE-2026-80564?
Apply the vendor's patch.
Is CVE-2026-80564 being exploited?
There is no known exploitation of CVE-2026-80564 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-80564, DEBIAN-CVE-2026-80564, UBUNTU-CVE-2026-80564.