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.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://www.zerodayinitiative.com/advisories/ZDI-23-1471/	Third Party Advisory
https://www.zerodayinitiative.com/advisories/ZDI-23-1471/	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:exim:exim:*:*:*:*:*:*:*:*

History

07 Aug 2025, 18:06

Type	Values Removed	Values Added
First Time		Exim exim Exim
CVSS	v2 : ~~unknown~~ v3 : ~~8.1~~	v2 : unknown v3 : 9.8
References	~~() https://www.zerodayinitiative.com/advisories/ZDI-23-1471/ -~~	() https://www.zerodayinitiative.com/advisories/ZDI-23-1471/ - Third Party Advisory
CPE		cpe:2.3:a:exim:exim::::::::

Information

Published : 2024-05-03 03:15

Updated : 2025-08-07 18:06

NVD link : CVE-2023-42117

Mitre link : CVE-2023-42117

CVE.ORG link : CVE-2023-42117

JSON object : View

Products Affected

exim

exim

CWE

CWE-138

Improper Neutralization of Special Elements

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