CVE-2020-28949 PEAR Archive_Tar: command or code injection
In plain words: The program treats text it receives as instructions instead of plain data. The attacker can run commands on the machine — often the whole device is taken over.
Confirmed exploited by CISA on · US federal patch deadline Sep 15, 2022
What to do
- Install PEAR's security update for Archive_Tar. If no update exists, follow the vendor's workaround or stop using the product until one ships.
- Keep a list of every internet-facing server you run so nothing is forgotten.
- Patch anything in this catalog first, ahead of normal patch cycles.
- Put admin and file-transfer apps behind a VPN or single sign-on instead of the open internet.
Who is affected
Work IT. Aimed mostly at company systems — you are affected through the companies you use, not your own phone.
What's at risk: Mass data theft and ransomware: a single flaw in a file-transfer or email server has exposed thousands of organisations at once.
The details
- Official name
- PEAR Archive_Tar Deserialization of Untrusted Data Vulnerability
- Product
- PEAR Archive_Tar
- CISA description
- 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.
- Type of flaw
- Command or code injection (CWE-74)
- Confirmed exploited
- Aug 25, 2022
- US federal patch deadline
- Sep 15, 2022
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Answering about CVE-2020-28949 ·
Questions about CVE-2020-28949
Is CVE-2020-28949 being exploited?
Yes. CISA added CVE-2020-28949 to its Known Exploited Vulnerabilities catalog on Aug 25, 2022, which means there is reliable evidence of real-world attacks.
How do I fix CVE-2020-28949?
Install PEAR's security update for Archive_Tar. If no update exists, follow the vendor's workaround or stop using the product until one ships. Keep a list of every internet-facing server you run so nothing is forgotten.
Am I affected by CVE-2020-28949?
Only if you use PEAR Archive_Tar. Aimed mostly at company systems — you are affected through the companies you use, not your own phone.