Known exploited · PEAR
CVE-2020-28949: PEAR Archive_Tar Deserialization of Untrusted Data Vulnerability
What it is
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.
- Vendor
- PEAR
- Product
- Archive_Tar
- Added to KEV
- August 25, 2022
- CISA due date
- September 15, 2022
- Ransomware use
- Unknown
What CISA requires
Apply updates per vendor instructions.
Forensic triage
No
What to do now
- Find every instance of Archive_Tar you run, including the forgotten ones, and check its version against the vendor advisory.
- Apply the vendor's fix or mitigation, before September 15, 2022 if you are bound by CISA's deadline, sooner if it faces the internet.
- Assume it was tried against you already: look for signs of exploitation from the date it was added, not from the day you patched.
References
H2 Security
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Start freeSource: CISA Known Exploited Vulnerabilities Catalog (public domain), catalog version 2026.10.01.