CVE-2021-27241 (GCVE-0-2021-27241)

Vulnerability from cvelistv5 – Published: 2021-03-29 21:05 – Updated: 2024-08-03 20:48
VLAI
Summary
This vulnerability allows local attackers to delete arbitrary directories on affected installations of Avast Premium Security 20.8.2429 (Build 20.8.5653.561). 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 AvastSvc.exe module. By creating a directory junction, an attacker can abuse the service to delete a directory. An attacker can leverage this vulnerability to create a denial-of-service condition on the system. Was ZDI-CAN-12082.
Severity
6.1 (Medium)
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H
CWE
  • CWE-59 - Improper Link Resolution Before File Access ('Link Following')
Assigner
zdi
References
Impacted products
Vendor Product Version
Avast Premium Security Affected: 20.8.2429 (Build 20.8.5653.561)
Create a notification for this product.
Credits
Abdelhamid Naceri
Show details on NVD website
To clipboard 

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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

Author Source Type Date Other

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.