CVE-2020-28949: in the CISA KEV catalogue
PEAR Archive_Tar Deserialization of Untrusted Data Vulnerability. CISA added CVE-2020-28949 to the Known Exploited Vulnerabilities catalogue on 2022-08-25 with a default due date of 2022-09-15. Known ransomware campaign use: Unknown. Forensic triage flag: No.
PEAR Archive_Tar allows an unserialization attack because phar: is blocked but PHAR: is not blocked. PEAR stands for PHP Extension and Application Repository and it is an open-source framework and distribution system for reusable PHP components with known usage in third-party products such as Drupal Core and Red Hat Linux. (CISA description)
- Vendor / product
- PEAR Archive_Tar
- CWE
- CWE-74
- CISA required action
- Apply updates per vendor instructions.
- EPSS
- 85%, percentile 99 (scored 2026-11-03)
EPSS puts about 85 in 100 odds (85%) on exploitation activity being observed in the next 30 days. Its score is higher than or equal to that of 99% 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-2020-28949 in the CISA KEV catalogue?
Yes. CISA added CVE-2020-28949 (PEAR Archive_Tar Deserialization of Untrusted Data Vulnerability) to the Known Exploited Vulnerabilities catalogue on 2022-08-25. CISA's default due date for it is 2022-09-15.
Is CVE-2020-28949 used in ransomware attacks?
CISA marks known ransomware campaign use as Unknown for CVE-2020-28949. That means CISA lacks confirmation, not that ransomware groups do not use it.
What should I do about CVE-2020-28949?
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-2020-28949