CVE-2026-80642 liveupdate: Reference count incoming FLB data
A use-after-free vulnerability in the Linux kernel's liveupdate subsystem allows local attackers to potentially execute code or escalate privileges.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-80642?
CVE-2026-80642 is an use after free vulnerability in Linux, published on 28 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:
liveupdate: Reference count incoming FLB data
Increment the incoming FLB refcount in liveupdate_flb_get_incoming() so that the FLB structure cannot be freed while the caller is actively using it. Add an additional liveupdate_flb_put_incoming() function so the caller can explicitly indicate when it is done using the FLB data.
During a Live Update, a subsystem might need to hold onto the incoming File-Lifecycle-Bound (FLB) data for an extended period, such as during device enumeration. Incrementing the reference count guarantees that the data remains valid and accessible until the subsystem releases it, preventing future use-after-free bugs.
Which versions are affected by CVE-2026-80642?
How do I fix CVE-2026-80642?
Apply the vendor's patch.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2026-80642 being exploited?
There is no known exploitation of CVE-2026-80642 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-80642, GHSA-pw7q-xpfh-rjvq, UBUNTU-CVE-2026-80642.