CVE-2026-89602 erofs: skip sufficiently large global buffers when resizing
A logic error in the Linux kernel EROFS filesystem causes a buffer overflow during resize retries, leading to a kernel crash and denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-89602?
CVE-2026-89602 is a high-severity vulnerability in Linux, published on 11 Sep 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Official description
In the Linux kernel, the following vulnerability has been resolved:
erofs: skip sufficiently large global buffers when resizing
z_erofs_gbuf_nrpages is advanced only after every global buffer has been grown. If a resize fails after some buffers were enlarged, a retry revisits those enlarged buffers.
Retrying the same size then returns -ENOMEM because alloc_pages_bulk() has no pages to add and the unchanged return value is treated as a failure. Retrying an intermediate size allocates a temporary pointer array smaller than gbuf->nrpages and copies more existing pointers than the array can hold.
Skip buffers that already satisfy the request. Once all remaining buffers have caught up, advancing z_erofs_gbuf_nrpages again describes the guaranteed minimum size across the pool.
Which versions are affected by CVE-2026-89602?
How do I fix CVE-2026-89602?
Apply the vendor's patch.
Is CVE-2026-89602 being exploited?
There is no known exploitation of CVE-2026-89602 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-89602, DEBIAN-CVE-2026-89602, GHSA-jv24-3qj8-gmg3, UBUNTU-CVE-2026-89602.