High severity · published Dec 27, 2021
CVE-2021-45335
Sandbox component in Avast Antivirus prior to 20.4 has an insecure permission which could be abused by local user to control the outcome of scans, and therefore evade detection or…
8.8
CVSS
0.4%
EPSS
No
On KEV
Description
Sandbox component in Avast Antivirus prior to 20.4 has an insecure permission which could be abused by local user to control the outcome of scans, and therefore evade detection or delete arbitrary system files.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 33% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AN
Antivirus · Avast
before 20.4 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-45335
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-45335
Exploit
https://github.com/the-deniss/Vulnerability-Disclosures/tree/main/CVE-2021-AVST3%20%26%20CVE-2021-AVST4%20%26%20CVE-2021-AVST5
Vendor Advisory
https://www.avast.com/hacker-hall-of-fame/en/researcher-david-eade-reports-antitrack-bug-to-avast-0
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