In PHP versions 7.2.x below 7.2.33, 7.3.x below 7.3.21 and 7.4.x below 7.4.9, while processing PHAR files using phar extension, phar_parse_zipfile could be tricked into accessing freed memory, which could lead to a crash or information disclosure.
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.
| Link | Tags |
|---|---|
| https://bugs.php.net/bug.php?id=79797 | mailing list patch vendor advisory exploit |
| https://security.gentoo.org/glsa/202009-10 | third party advisory vendor advisory |
| https://security.netapp.com/advisory/ntap-20200918-0005/ | third party advisory |
| https://www.debian.org/security/2021/dsa-4856 | third party advisory vendor advisory |
| https://www.tenable.com/security/tns-2021-14 | third party advisory patch |