High severity · published Dec 27, 2021
CVE-2021-45339
Privilege escalation vulnerability in Avast Antivirus prior to 20.4 allows a local user to gain elevated privileges by "hollowing" trusted process which could lead to the…
7.8
CVSS
0.3%
EPSS
No
On KEV
Description
Privilege escalation vulnerability in Avast Antivirus prior to 20.4 allows a local user to gain elevated privileges by "hollowing" trusted process which could lead to the bypassing of Avast self-defense.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 26% 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-2021-45339
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-45339
Exploit
https://github.com/the-deniss/Vulnerability-Disclosures/tree/main/CVE-2021-AVST0
Vendor Advisory
https://www.avast.com/hacker-hall-of-fame/en/researcher-david-eade-reports-antitrack-bug-to-avast-0
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