CVE-2020-10543

Perl before 5.30.3 on 32-bit platforms allows a heap-based buffer overflow because nested regular expression quantifiers have an integer overflow.

A heap buffer overflow vulnerability exists in the regular expression compiler of Perl packages shipped with Red Hat Enterprise Linux 6, 7, and 8. The flaw occurs in the S_study_chunk() function of regcomp.c due to a signed size_t integer overflow in storage space calculations for nested regular expression quantifiers. When untrusted regular expressions are compiled, this can lead to out-of-bounds memory writes with attacker-controlled data. The vulnerability does not depend on the data being matched, but rather on the regular expression itself. On Red Hat systems, this could result in denial of service or potential code execution when processing malicious regular expressions. Red Hat customers should not allow untrusted regular expressions to be compiled by the Perl regular expression compiler, as regular expressions in Perl can contain arbitrary code.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

To mitigate this flaw, developers should not allow untrusted regular expressions to be compiled by the Perl regular expression compiler.