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CVE-2026-52937 (GCVE-0-2026-52937)

Vulnerability from cvelistv5 – Published: 2026-06-24 07:14 – Updated: 2026-06-24 07:14
VLAI
Title
tap: fix stack info leak in tap_ioctl() SIOCGIFHWADDR
Summary
In the Linux kernel, the following vulnerability has been resolved: tap: fix stack info leak in tap_ioctl() SIOCGIFHWADDR In the SIOCGIFHWADDR path, tap_ioctl() copies 16 bytes of an uninitialised on-stack struct sockaddr_storage to userspace via ifr_hwaddr, but netif_get_mac_address() only writes sa_family and dev->addr_len (6 for Ethernet) bytes, leaving sa_data[6..13] uninitialised. Those 8 trailing bytes leak kernel stack contents; SIOCGIFHWADDR on a macvtap chardev returns kernel .text and direct-map pointers, defeating KASLR. Initialise ss at declaration.
Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 3b23a32a63219f51a5298bc55a65ecee866e79d0 , < 719007c3492f0f1f9e9cdbed8ac45ba45bb13eeb (git)
Affected: 3b23a32a63219f51a5298bc55a65ecee866e79d0 , < 05305e832be7b9d65b2b72caacf7d850b3942b2a (git)
Affected: 3b23a32a63219f51a5298bc55a65ecee866e79d0 , < bddc09212c24934643bd44fc794748d2bbb3b6cd (git)
Affected: 176188cff67ec1aa55103647b61d02315cc38e98 (git)
Affected: 1fc205d9e400f069ebf30d3faa6ec2bab2cbd7b4 (git)
Affected: 4d0ae760c02c98fc78b78d3a0509896bc648ad1c (git)
Affected: 5.4.103 , < 5.5 (semver)
Affected: 5.10.21 , < 5.11 (semver)
Affected: 5.11.4 , < 5.12 (semver)
guessed Create a notification for this product.
Linux Linux Affected: 5.12
Unaffected: 0 , < 5.12 (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.
Show details on NVD website
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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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