Learn about CVE-2023-38545, a critical heap buffer overflow vulnerability in curl, impacting versions 8.4.0 and below. Understand the impact, affected systems, and mitigation steps.
This article discusses a critical heap buffer overflow vulnerability in curl, a popular command-line tool for transferring data with URL syntax.
Understanding CVE-2023-38545
This vulnerability allows an attacker to trigger a heap-based buffer overflow in the SOCKS5 proxy handshake process in curl.
What is CVE-2023-38545?
The flaw in curl leads to an overflow in a heap-based buffer during the SOCKS5 proxy handshake. This occurs when curl attempts to relay the host name to the SOCKS5 proxy, allowing resolution by the host instead of curl itself.
The Impact of CVE-2023-38545
The vulnerability could be exploited by an attacker to execute arbitrary code or cause a denial of service (DoS) condition on systems running the affected versions of curl.
Technical Details of CVE-2023-38545
This section delves into the specifics of the vulnerability, including affected systems, versions, and the exploitation mechanism.
Vulnerability Description
When curl encounters a host name longer than 255 bytes during the SOCKS5 handshake, a local variable can be manipulated to copy the oversized host name into a target buffer, leading to a heap buffer overflow.
Affected Systems and Versions
The vulnerability affects curl version 8.4.0 and prior, while versions below 7.69.0 are not impacted.
Exploitation Mechanism
By crafting a malicious request with an excessively long host name, an attacker can exploit the vulnerability to corrupt memory and potentially execute arbitrary code.
Mitigation and Prevention
To secure systems from CVE-2023-38545, immediate actions and long-term security practices are essential.
Immediate Steps to Take
Affected users are advised to update curl to a non-vulnerable version, apply patches if available, and monitor for any signs of exploitation.
Long-Term Security Practices
Practicing defense-in-depth strategies, conducting regular security audits, and staying informed about software vulnerabilities can help mitigate risks associated with such vulnerabilities.
Patching and Updates
Stay informed about security advisories from the vendor and promptly apply patches to address known vulnerabilities.