Integer overflow in Linux
CVE-2025-21736
In the Linux kernel, the following vulnerability has been resolved: nilfs2: fix possible int overflows in nilfs_fiemap() Since nilfs_bmap_lookup_contig() in nilfs_fiemap() calculates its result by being prepared to go through potentially maxblocks == INT_MAX blocks, the value in n may experience an overflow caused by left shift of blkbits. While it is extremely unlikely to occur, play it safe and cast right hand expression to wider type to mitigate the issue. Found by Linux Verification Center (linuxtesting.org) with static analysis tool SVACE.
Vulnerability class: Integer Overflow
EPSS: 0.002 (13.6th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.
Affected products
- Linux — versions 622daaff0a8975fb5c5b95f24f3234550ba32e92, 2.6.38, 0
- Linux Linux_kernel
Weakness classification (CWE)
Public proof-of-concept exploits
References
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
- af854a3a-2127-422b-91ae-364da2661108
- af854a3a-2127-422b-91ae-364da2661108
Frequently asked questions
- What is CVE-2025-21736?
- CVE-2025-21736 is a medium-severity vulnerability in Linux, classified under Integer Overflow or Wraparound. CVSS score: 5.5/10. Published 2025-02-27.
- How severe is CVE-2025-21736?
- Medium severity. CVSS v3 base score is 5.5 out of 10.
- Is CVE-2025-21736 known to be exploited?
- 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.