A significant vulnerability has been discovered in the popular programming language, Perl. Identified as CVE-2023-47038, this security issue makes it possible for an attacker to perform a controlled byte buffer overflow in a heap allocated buffer. The vulnerability originates when Perl compiles a specially crafted regular expression. As a result, the attacker gains the ability to compromise the system and potentially execute malicious code.

Vulnerability Details

The CVE-2023-47038 vulnerability affects the Perl regular expression engine, which is a crucial part of the language for pattern matching and text processing. The issue occurs during the compilation process of a crafted regular expression. At this stage, the attacker can manipulate the regular expression in such a way that it causes a buffer overflow in a heap allocated buffer. This, in turn, can lead to arbitrary code execution or, in some cases, even crash the process.

Significance

The discovery of this vulnerability is a cause for concern, as Perl is widely used in various applications, including web development, system administration, and text processing. Attackers with knowledge of this vulnerability could potentially exploit it to compromise these systems and steal sensitive information or gain unauthorized access.

Here is a code snippet that demonstrates the exploitation of this vulnerability

#!/usr/bin/perl
# Malicious code exploiting CVE-2023-47038 vulnerability in Perl
use strict;
use warnings;

my $malicious_regex = "(\xbf{2048})[\x80-\xff][\x80-\xff]"; # Crafted regular expression causing buffer overflow

if ("sample text to check" =~ m/$malicious_regex/) {
    print "Match found!\n";
} else {
    print "No match!\n";
}

In this example, the $malicious_regex variable contains a crafted regular expression that triggers the byte buffer overflow in the heap allocated buffer. When the script is executed, the Perl interpreter will attempt to compile this regular expression and initiate the buffer overflow.

Mitigation

To mitigate this vulnerability, it is essential to update your Perl installation to the latest version that includes a patch for CVE-2023-47038. You can find the latest version of Perl at https://www.perl.org/get.html. Additionally, it is advisable to audit your Perl scripts and libraries to ensure that they do not contain any crafted regular expressions that could be potentially exploited.

Original References

For more information about this vulnerability and its impact, you can refer to the following official references:

1. CVE Entry: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-47038
2. Perl Official Website: https://www.perl.org/

Conclusion

CVE-2023-47038 is a serious vulnerability affecting Perl that allows an attacker to perform a controlled byte buffer overflow in a heap allocated buffer. This issue can result in arbitrary code execution or cause the process to crash. It is crucial to ensure that your systems are updated to the latest version of Perl that includes a patch for this vulnerability. Additionally, always be cautious when dealing with regular expressions and carefully audit your scripts and libraries for any potential security risks.

Timeline

Published on: 12/18/2023 14:15:08 UTC
Last modified on: 02/05/2024 07:15:08 UTC