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)
guessed Create a notification for this product.
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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      "source": "SUSE CSAF VEX",
      "status": "interim",
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      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-64082.json",
      "version": "5"
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}



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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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  • 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.


Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.