f2fs: validate MOVE_RANGE destination size
CVE-2026-89840 · published 16 Sept 2026
How serious is it
- Severity: high, CVSS score 7.1 out of 10.
- No exploit prediction (EPSS) score yet.
- Not on the CISA list of exploited vulnerabilities.
- No public exploit in Exploit-DB.
Is your app affected by CVE-2026-89840?
Paste this prompt into Claude Code, Cursor or any AI coding tool: it runs a free Shippable scan of your project and fixes what it finds. Built with Lovable, Bolt or v0? Scan your live app. Or upload your package file.
Who is affected
- Linux Linux: 4dd6f977fc778e5a0da604e5f8cb2f36d163d27b to < 54c587f3f95ce2d6932a16566db83f73cc4313e1, 4dd6f977fc778e5a0da604e5f8cb2f36d163d27b to < bca61ee5192ea47003722486ae9588a2a4bb47b6, 4dd6f977fc778e5a0da604e5f8cb2f36d163d27b to < db13064669526494cd78ba3a4394063b740e940c, 4dd6f977fc778e5a0da604e5f8cb2f36d163d27b to < dcae1eeda53149f219dd6af93b3083b7271c1c63
- Linux Linux: 4.8
How to check
- Find out whether you run the affected product and which version, then compare it with the versions above.
How to fix
Copies a prompt for Claude Code, Cursor or Codex that asks it to check whether you run this product.
- Apply the vendor's update or mitigation from the references below. If there is none yet, limit exposure of the affected service until there is.
- If a vulnerable version was live, check your logs and rotate the secrets that server could read.
The advisory
In the Linux kernel, the following vulnerability has been resolved:
f2fs: validate MOVE_RANGE destination size
F2FS_IOC_MOVE_RANGE checks the source range, but not the destination end
before updating i_size. A source hole can expose this: __clone_blkaddrs()
skips NULL_ADDR entries and returns success, so the caller can still extend
the destination inode with unchecked pos_out + len.
Reject destination overflow and use inode_newsize_ok() before extending
the destination inode.
Check your whole app
Dependencies are only half of it. Free and read-only: before you push, run npx shippable-dev scan localhost:3000 in your project folder, no account needed. For your live app, you prove it's yours with a one-line tag first.
References
- git.kernel.org/stable/c/54c587f3f95ce2d6932a16566db83f73cc4313e1
- git.kernel.org/stable/c/bca61ee5192ea47003722486ae9588a2a4bb47b6
- git.kernel.org/stable/c/db13064669526494cd78ba3a4394063b740e940c
- git.kernel.org/stable/c/dcae1eeda53149f219dd6af93b3083b7271c1c63
- git.kernel.org/stable/c/e533889fc26aea0cd83c90327063f272061dd820
Merged from CVE List. Last updated 26 Oct 2026. All vulnerabilities · RSS · JSON