CVE-2026-98777 binder: fix leaked fd fixups on TF_UPDATE_TXN supersede
A local attacker can trigger a memory leak in the Linux kernel binder driver, leading to file descriptor exhaustion and denial of service.
- 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-2026-98777?
CVE-2026-98777 is a memory corruption vulnerability in Linux, published on 18 Oct 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:
binder: fix leaked fd fixups on TF_UPDATE_TXN supersede
When a TF_UPDATE_TXN transaction supersedes a pending async transaction in a frozen process, the outdated transaction is freed with kfree() directly. This skips binder_free_txn_fixups(), leaking all binder_txn_fd_fixup entries and their fget()'d struct file references.
The leaked file refcounts never reach zero, so the struct file objects are permanently pinned in memory. They survive process exit and accumulate across invocations until file-max exhaustion.
Every other transaction cleanup path (binder_free_transaction(), binder_transaction() error paths, binder_release_work()) correctly calls binder_free_txn_fixups(). Add the missing call before kfree() in the t_outdated cleanup block.
Which versions are affected by CVE-2026-98777?
How do I fix CVE-2026-98777?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-98777 being exploited?
There is no known exploitation of CVE-2026-98777 in the wild and no public exploit code.
Sources
Also known as AZL-108683, BELL-CVE-2026-98777, DEBIAN-CVE-2026-98777, GHSA-crhv-x2gr-r2gm, UBUNTU-CVE-2026-98777.