CVE-2021-34866 (GCVE-0-2021-34866)

Vulnerability from cvelistv5 – Published: 2022-01-25 15:30 – Updated: 2024-08-04 00:26
VLAI
Summary
This vulnerability allows local attackers to escalate privileges on affected installations of Linux Kernel 5.14-rc3. An attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit this vulnerability. The specific flaw exists within the handling of eBPF programs. The issue results from the lack of proper validation of user-supplied eBPF programs, which can result in a type confusion condition. An attacker can leverage this vulnerability to escalate privileges and execute arbitrary code in the context of the kernel. Was ZDI-CAN-14689.
Severity
8.8 (High)
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
CWE
  • CWE-843 - Access of Resource Using Incompatible Type ('Type Confusion')
Assigner
zdi
References
Impacted products
Vendor Product Version
Linux Kernel Affected: 5.14-rc3
Create a notification for this product.
Credits
Ryota Shiga(@Ga_ryo_) of Flatt Security
Show details on NVD website
To clipboard 

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    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2025-11-21T14:54:12+00:00",
      "cve": "CVE-2021-34866",
      "id": "CVE-2021-34866",
      "initial_release_date": "2021-10-13T12:00:00+00:00",
      "product_status:fixed": "297",
      "product_status:known_affected": "182",
      "product_status:known_not_affected": "39",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: eBPF verification flaw",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2021/cve-2021-34866.json",
      "version": "3"
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}



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Sightings

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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.


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