CVE-2025-21734 (GCVE-0-2025-21734)

Vulnerability from cvelistv5 – Published: 2025-02-27 02:12 – Updated: 2026-08-05 11:54
VLAI
Title
misc: fastrpc: Fix copy buffer page size
Summary
In the Linux kernel, the following vulnerability has been resolved: misc: fastrpc: Fix copy buffer page size For non-registered buffer, fastrpc driver copies the buffer and pass it to the remote subsystem. There is a problem with current implementation of page size calculation which is not considering the offset in the calculation. This might lead to passing of improper and out-of-bounds page size which could result in memory issue. Calculate page start and page end using the offset adjusted address instead of absolute address.
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 02b45b47fbe84e23699bb6bdc74d4c2780e282b4 , < c56ba3ea8e3c9a69a992aad18f7a65e43e51d623 (git)
Affected: 02b45b47fbe84e23699bb6bdc74d4c2780e282b4 , < c0464bad0e85fcd5d47e4297d1e410097c979e55 (git)
Affected: 02b45b47fbe84e23699bb6bdc74d4c2780e282b4 , < 24a79c6bc8de763f7c50f4f84f8b0c183bc25a51 (git)
Affected: 02b45b47fbe84e23699bb6bdc74d4c2780e282b4 , < c3f7161123fcbdc64e90119ccce292d8b66281c4 (git)
Affected: 02b45b47fbe84e23699bb6bdc74d4c2780e282b4 , < e966eae72762ecfdbdb82627e2cda48845b9dd66 (git)
Create a notification for this product.
Linux Linux Affected: 5.2
Unaffected: 0 , < 5.2 (semver)
Unaffected: 6.1.129 , ≤ 6.1.* (semver)
Unaffected: 6.6.78 , ≤ 6.6.* (semver)
Unaffected: 6.12.14 , ≤ 6.12.* (semver)
Unaffected: 6.13.3 , ≤ 6.13.* (semver)
Unaffected: 6.14 , ≤ * (original_commit_for_fix)
Create a notification for this product.
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      "title": "kernel: misc: fastrpc: Fix copy buffer page size",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-21734.json",
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}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.