CVE-2023-51765 : What You Need to Know
Learn about CVE-2023-51765, a vulnerability in sendmail allowing SMTP smuggling in certain configurations, enabling attackers to spoof e-mail addresses and bypass SPF protections.
A detailed overview of CVE-2023-51765, covering its impact, technical details, and mitigation strategies.
Understanding CVE-2023-51765
CVE-2023-51765 pertains to a vulnerability in sendmail through 8.17.2 that allows for SMTP smuggling in specific configurations.
What is CVE-2023-51765?
The CVE-2023-51765 vulnerability enables remote attackers to carry out SMTP smuggling by injecting spoofed e-mail messages with a spoofed MAIL FROM address, thus bypassing SPF protection mechanisms. This arises due to disparities in email server support for certain protocols.
The Impact of CVE-2023-51765
The exploitation of CVE-2023-51765 can lead to unauthorized injection of e-mail messages, potentially circumventing email security measures such as SPF protection.
Technical Details of CVE-2023-51765
CVE-2023-51765 involves the sendmail software through version 8.17.2 and its susceptibility to SMTP smuggling. The issue is resolved in version 8.18 and subsequent releases with specific features implemented.
Vulnerability Description
The vulnerability allows for the injection of e-mail messages with spoofed addresses, exploiting differences in email server support for certain protocols.
Affected Systems and Versions
The vulnerability impacts sendmail versions up to 8.17.2 where certain configurations enable SMTP smuggling.
Exploitation Mechanism
Remote attackers can exploit the vulnerability to inject e-mail messages with spoofed MAIL FROM addresses, leveraging the <LF>.<CR><LF> support in sendmail.
Mitigation and Prevention
Take immediate action to address and prevent potential exploits of CVE-2023-51765.
Immediate Steps to Take
Update sendmail to version 8.18 or later to mitigate the vulnerability and prevent SMTP smuggling attacks.
Long-Term Security Practices
Implement robust email security measures and protocols to protect against SMTP smuggling and similar attacks.
Patching and Updates
Regularly apply software patches and updates to ensure that known vulnerabilities are addressed and mitigated effectively.