Auth bypass in Avast Antivirus
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 bypassing of Avast self-defense.
Vulnerability class: Broken Access Control
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.003 (22.0th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 22nd percentile — 22.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000
Affected products
Weakness classification (CWE)
References
- www.avast.com/hacker-hall-of-fame/en/researcher-david-eade-reports-antitrack-bu… (Vendor Advisory)
- github.com/the-deniss/Vulnerability-Disclosures/tree/main/CVE-2021-AVST0 (Exploit, Third Party Advisory)
Frequently asked questions
- What is CVE-2021-45339?
- CVE-2021-45339 is a high-severity vulnerability in Avast Antivirus, classified under Incorrect Authorization. CVSS score: 7.8/10. Published 2021-12-27.
- How severe is CVE-2021-45339?
- High severity. CVSS v3 base score is 7.8 out of 10.