CVE-2023-42117

Description

Exim Improper Neutralization of Special Elements Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of Exim. Authentication is not required to exploit this vulnerability. The specific flaw exists within the smtp service, which listens on TCP port 25 by default. The issue results from the lack of proper validation of user-supplied data, which can result in a memory corruption condition. An attacker can leverage this vulnerability to execute code in the context of the current process. Was ZDI-CAN-17554.

CVSS v3.1 Score

9.8

CRITICAL

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Weakness Type (CWE)

CWE-138 CWE-138

Affected Products

Vendor	Product	Versions
exim	exim	< 4.96.2

References

Other References

https://www.zerodayinitiative.com/advisories/ZDI-23-1471/ https://lists.debian.org/debian-lts-announce/2024/10/msg00029.html https://www.zerodayinitiative.com/advisories/ZDI-23-1471/

Frequently Asked Questions

What is CVE-2023-42117? +

Exim Improper Neutralization of Special Elements Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of Exim. Authentication is not required to exploit this vulnerability. The specific flaw exists within the smtp service, which listens on TCP port 25 by default. The issue results from the lack of proper validation of user-supplied data, which can result in a memory corruption condition. An attacker can leverage this vulnerability to execute code in the context of the current process. Was ZDI-CAN-17554. It has a CVSS v3.1 base score of 9.8 (CRITICAL).

How severe is CVE-2023-42117? +

CVE-2023-42117 has a CVSS v3.1 score of 9.8 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately.

What products are affected by CVE-2023-42117? +

CVE-2023-42117 affects products from exim, specifically: exim. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2023-42117? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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