CVE-2025-21874: Linux kernel · dm-integrity: Avoid divide by zero in table status in Inline mode
Source GCVE Database
Not known to be exploited · CVSS 5.5 Medium.
Data as of 29 Oct 2026, 23:15 UTC
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 27 Mar 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.
What to do
AI-suggested
Until a fix is available, avoid running dm-integrity in Inline mode or refrain from executing device-mapper table queries that trigger the vulnerability.
Description
CVE-2025-21874 is a vulnerability in the Linux kernel's dm-integrity module where a divide-by-zero error can occur in Inline mode when querying the device-mapper table status. This happens because the calculation of the journal watermark divides by journal_sectors, which is zero in Inline mode since the journal is unused. The flaw can cause a kernel crash (OOPS) when running a simple table query such as 'dmsetup table'.
References
- nvd.nist.gov/vuln/detail/CVE-2025-21874 (opens in a new tab)
- git.kernel.org/stable/c/06d9895f265282e939a8933bb18de82eba2b4dda (opens in a new tab)
- git.kernel.org/stable/c/22c6f577b3cb184857b440ae5e5916f6c9e7021d (opens in a new tab)
- git.kernel.org/stable/c/7fb39882b20c98a9a393c244c86b56ef6933cff8 (opens in a new tab)