CVE-2021-0920 (GCVE-0-2021-0920)

Vulnerability from cvelistv5 – Published: 2021-12-15 18:05 – Updated: 2025-10-21 23:15
VLAI CISA KEV
Summary
In unix_scm_to_skb of af_unix.c, there is a possible use after free bug due to a race condition. This could lead to local escalation of privilege with System execution privileges needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android kernelAndroid ID: A-196926917References: Upstream kernel
Severity
6.4 (Medium)
CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H
CWE
  • Elevation of privilege
Assigner
References
Impacted products
Vendor Product Version
n/a Android Affected: Android kernel
CISA KEV
Known Exploited Vulnerability - GCVE BCP-07 Compliant
KEV entry ID: fb26cf7c-2569-40f7-8c45-7b65c2a1b543

Vulnerability ID: CVE-2021-0920

Status: Confirmed

Status Updated: 2022-05-23 00:00 UTC

Exploited: Yes

Timestamps
First Seen: 2022-05-23
Asserted: 2022-05-23
Scope
Notes: KEV entry: Android Kernel Race Condition Vulnerability | Affected: Android / Kernel | Description: Android kernel contains a race condition, which allows for a use-after-free vulnerability. Exploitation can allow for privilege escalation. | Required action: Apply updates per vendor instructions. | Due date: 2022-06-13 | Known ransomware campaign use (KEV): Unknown | Notes (KEV): https://nvd.nist.gov/vuln/detail/CVE-2021-0920
Evidence

Type: Vendor Report

Signal: Successful Exploitation

Confidence: 80%

Source: cisa-kev

Details
Cwes CWE-362 CWE-416
Feed CISA Known Exploited Vulnerabilities Catalog
Product Kernel
Due Date 2022-06-13
Date Added 2022-05-23
Vendorproject Android
Vulnerabilityname Android Kernel Race Condition Vulnerability
Knownransomwarecampaignuse Unknown
References
Created: 2026-02-02 13:25 UTC | Updated: 2026-02-06 07:53 UTC
Show details on NVD website
To clipboard 

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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.