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CVE-2026-64082 (GCVE-0-2026-64082)

Vulnerability from cvelistv5 – Published: 2026-07-19 15:39 – Updated: 2026-09-02 12:49
VLAI
Title
riscv: Fix register corruption from uninitialized cregs on error
Summary
In the Linux kernel, the following vulnerability has been resolved: riscv: Fix register corruption from uninitialized cregs on error compat_riscv_gpr_set() calls cregs_to_regs() unconditionally, even when user_regset_copyin() fails. Since cregs is an uninitialized stack variable, a copyin failure causes uninitialized stack data to be written into the target task's pt_regs, corrupting its register state and potentially leaking kernel stack contents. compat_restore_sigcontext() has the same issue: it calls cregs_to_regs() even when __copy_from_user() fails, leading to the same corruption of the signal-returning task's register state on error. Only call cregs_to_regs() when the user copy succeeds.
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 CPE status
Linux Linux Affected: 7383ee05314be58f8f9f018ee0ac53bef3808aea , < f2d88b0d7aebfa4643fc58bbae57210c6daff9c6 (git)
Affected: 7383ee05314be58f8f9f018ee0ac53bef3808aea , < 66dedb6028c3df6c6a3372dd935b823917e150d5 (git)
Affected: 7383ee05314be58f8f9f018ee0ac53bef3808aea , < 2a7d1daf2674fe7d5b1cc99a4e3b5f0f72d5958f (git)
Affected: 7383ee05314be58f8f9f018ee0ac53bef3808aea , < 0599aa23734c48de9bce36d043a9ec90c23945a1 (git)
Affected: 7383ee05314be58f8f9f018ee0ac53bef3808aea , < 9e020156833f1ad0d425a1e3d85b65639f1c1c50 (git)
Affected: 7383ee05314be58f8f9f018ee0ac53bef3808aea , < 6ebcbb53fc9bc30843054ed99fd60b8e542628f4 (git)
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Linux Linux Affected: 5.19
Unaffected: 0 , < 5.19 (semver)
Unaffected: 6.1.187 , ≤ 6.1.* (semver)
Unaffected: 6.6.156 , ≤ 6.6.* (semver)
Unaffected: 6.12.108 , ≤ 6.12.* (semver)
Unaffected: 6.18.49 , ≤ 6.18.* (semver)
Unaffected: 7.0.11 , ≤ 7.0.* (semver)
Unaffected: 7.1 , ≤ * (original_commit_for_fix)
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      "cve": "CVE-2026-64082",
      "id": "CVE-2026-64082",
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      "product_status:known_not_affected": "274",
      "source": "Red Hat CSAF VEX",
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      "title": "kernel: riscv: Fix register corruption from uninitialized cregs on error",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-64082.json",
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    }
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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

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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.