CVE-2020-2021: in the CISA KEV catalogue
Palo Alto Networks PAN-OS Authentication Bypass Vulnerability. CISA added CVE-2020-2021 to the Known Exploited Vulnerabilities catalogue on 2022-03-25 with a default due date of 2022-04-15. Known ransomware campaign use: Known. Forensic triage flag: No.
Palo Alto Networks PAN-OS contains a vulnerability in SAML which allows an attacker to bypass authentication. (CISA description)
- Vendor / product
- Palo Alto Networks PAN-OS
- CWE
- CWE-347
- CISA required action
- Apply updates per vendor instructions.
- EPSS
- 4.4%, percentile 91 (scored 2026-11-03)
EPSS puts about 4.4 in 100 odds (4.4%) on exploitation activity being observed in the next 30 days. Its score is higher than or equal to that of 91% of scored CVEs. This is a model estimate about exploitation anywhere, not about your environment.
Vendor and reference links (from CISA)
Your own deadline under CISA BOD 26-04 depends on exposure, automatability and technical impact: work it out with the BOD 26-04 calculator.
Frequently asked questions
Is CVE-2020-2021 in the CISA KEV catalogue?
Yes. CISA added CVE-2020-2021 (Palo Alto Networks PAN-OS Authentication Bypass Vulnerability) to the Known Exploited Vulnerabilities catalogue on 2022-03-25. CISA's default due date for it is 2022-04-15.
Is CVE-2020-2021 used in ransomware attacks?
CISA marks known ransomware campaign use as Known for CVE-2020-2021.
What should I do about CVE-2020-2021?
CISA's required action: Apply updates per vendor instructions.
Sources
- CISA, Known Exploited Vulnerabilities Catalog (accessed 2026-11-03)
- FIRST, Exploit Prediction Scoring System (EPSS) (EPSS by FIRST; scores generated by Empirical Security)
- NVD record for CVE-2020-2021