CVE-2026-89840
HIGH
Published Sep 16, 2026
Modified Sep 21, 2026
Description
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.
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CVSS v3.1 Score
7.1
HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
EPSS — Exploit Prediction
0.0017
Probability of exploitation
0.06%
Percentile rank
EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.
References
Frequently Asked Questions
What is CVE-2026-89840? +
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. It has a CVSS v3.1 base score of 7.1 (HIGH).
How severe is CVE-2026-89840? +
CVE-2026-89840 has a CVSS v3.1 score of 7.1 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0017, placing it in the 0th percentile for exploitation probability.
How do I check if I'm vulnerable to CVE-2026-89840? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.
