CVE-2025-39815 (GCVE-0-2025-39815)

Vulnerability from cvelistv5 – Published: 2025-09-16 13:00 – Updated: 2026-05-11 21:36
VLAI
Title
RISC-V: KVM: fix stack overrun when loading vlenb
Summary
In the Linux kernel, the following vulnerability has been resolved: RISC-V: KVM: fix stack overrun when loading vlenb The userspace load can put up to 2048 bits into an xlen bit stack buffer. We want only xlen bits, so check the size beforehand.
Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 2fa290372dfe7dd248b1c16f943f273a3e674f22 , < c76bf8359188a11f8fd790e5bbd6077894a245cc (git)
Affected: 2fa290372dfe7dd248b1c16f943f273a3e674f22 , < 6d28659b692a0212f360f8bd8a58712b339f9aac (git)
Affected: 2fa290372dfe7dd248b1c16f943f273a3e674f22 , < 799766208f09f95677a9ab111b93872d414fbad7 (git)
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Linux Linux Affected: 6.8
Unaffected: 0 , < 6.8 (semver)
Unaffected: 6.12.45 , ≤ 6.12.* (semver)
Unaffected: 6.16.5 , ≤ 6.16.* (semver)
Unaffected: 6.17 , ≤ * (original_commit_for_fix)
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Tags
Taxonomy of the tags.





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.