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CVE-2026-64134 (GCVE-0-2026-64134)

Vulnerability from cvelistv5 – Published: 2026-07-19 15:40 – Updated: 2026-08-05 12:39
VLAI
Title
ALSA: pcm: Don't setup bogus iov_iter for silencing
Summary
In the Linux kernel, the following vulnerability has been resolved: ALSA: pcm: Don't setup bogus iov_iter for silencing At transition to the iov_iter for PCM data transfer, we blindly applied the iov_iter setup also for silencing (i.e. data = NULL), and it leads to a calculation of bogus iov_iter. Fortunately this didn't cause troubles on most of architectures but it goes wrong on RISC-V now, causing a NULL dereference. Handle the NULL data case to treat the silencing in interleaved_copy() for addressing the bug above. noninterleaved_copy() has already the NULL data handling, so it doesn't need changes.
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: cf393babb37a1679a1ec1d864df1090353465e23 , < 41a766c647294842c9b17672449f8e011048cba9 (git)
Affected: cf393babb37a1679a1ec1d864df1090353465e23 , < ce836587e594af39ff048d9b29dee0f5f10692c9 (git)
Affected: cf393babb37a1679a1ec1d864df1090353465e23 , < feff0251386aa6bb180a0a1cf7c1f91ba868113d (git)
Affected: cf393babb37a1679a1ec1d864df1090353465e23 , < c9f6768515818d71bdfc20119a81f3332c53b9c6 (git)
Affected: cf393babb37a1679a1ec1d864df1090353465e23 , < e4d3386b74fba8e01280484b67ee481ece00201e (git)
guessed Create a notification for this product.
Linux Linux Affected: 6.6
Unaffected: 0 , < 6.6 (semver)
Unaffected: 6.6.142 , ≤ 6.6.* (semver)
Unaffected: 6.12.92 , ≤ 6.12.* (semver)
Unaffected: 6.18.34 , ≤ 6.18.* (semver)
Unaffected: 7.0.11 , ≤ 7.0.* (semver)
Unaffected: 7.1 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
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      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: ALSA: pcm: Don\u0027t setup bogus iov_iter for silencing",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-64134.json",
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      "status": "interim",
      "title": "SUSE CVE CVE-2026-64134",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-64134.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.

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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.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • 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.


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