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CVE-2026-64255 (GCVE-0-2026-64255)

Vulnerability from cvelistv5 – Published: 2026-07-24 15:31 – Updated: 2026-08-17 04:52
VLAI
Title
wifi: iwlwifi: mld: validate sta_mask before ffs() in BA session handlers
Summary
In the Linux kernel, the following vulnerability has been resolved: wifi: iwlwifi: mld: validate sta_mask before ffs() in BA session handlers Three BA session handlers use ffs(ba_data->sta_mask) - 1 to derive a station ID without checking that sta_mask is non-zero. When sta_mask is zero, ffs() returns 0 and the subtraction wraps to 0xFFFFFFFF, causing an out-of-bounds access on fw_id_to_link_sta[]. Add WARN_ON_ONCE(!ba_data->sta_mask) guards before each ffs() call, consistent with the existing check in iwl_mld_ampdu_rx_start().
Severity
8.8 (High)
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 9aa3856d9b6f3f8bf085b5bbb5f3703578bf452b , < 1de92789ce31e46fa7e7d8e89c90b19cdb1c103b (git)
Affected: 9aa3856d9b6f3f8bf085b5bbb5f3703578bf452b , < fe7f339f63c9dc4ca546ed7ac38ba4bb3a99dcfc (git)
Affected: 9aa3856d9b6f3f8bf085b5bbb5f3703578bf452b , < f056fc2b927448d37eca6b6cacc3d1b0f67b20d2 (git)
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Linux Linux Affected: 6.4
Unaffected: 0 , < 6.4 (semver)
Unaffected: 6.18.38 , ≤ 6.18.* (semver)
Unaffected: 7.1.3 , ≤ 7.1.* (semver)
Unaffected: 7.2 , ≤ * (original_commit_for_fix)
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{
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          "product": "Linux",
          "programFiles": [
            "drivers/net/wireless/intel/iwlwifi/mld/agg.c"
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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.


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