CVE-2023-42118

Exim libspf2 Integer Underflow Remote Code Execution Vulnerability. This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of Exim libspf2. Authentication is not required to exploit this vulnerability. The specific flaw exists within the parsing of SPF macros. When parsing SPF macros, the process does not properly validate user-supplied data, which can result in an integer underflow before writing to memory. An attacker can leverage this vulnerability to execute code in the context of the service account. . Was ZDI-CAN-17578.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector ADJACENT_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-23-1472/	Third Party Advisory
http://www.openwall.com/lists/oss-security/2025/03/28/1	Mailing List
https://www.zerodayinitiative.com/advisories/ZDI-23-1472/	Third Party Advisory

Configurations

Configuration 1 (hide)

AND

cpe:2.3:a:libspf2_project:libspf2:-:*:*:*:*:*:*:*

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

History

07 Aug 2025, 18:17

Type	Values Removed	Values Added
CPE		cpe:2.3:a:exim:exim:-:::::::* cpe:2.3:a:libspf2_project:libspf2:-:::::::*
References	~~() https://www.zerodayinitiative.com/advisories/ZDI-23-1472/ -~~	() https://www.zerodayinitiative.com/advisories/ZDI-23-1472/ - Third Party Advisory
References	~~() http://www.openwall.com/lists/oss-security/2025/03/28/1 -~~	() http://www.openwall.com/lists/oss-security/2025/03/28/1 - Mailing List
CVSS	v2 : ~~unknown~~ v3 : ~~7.5~~	v2 : unknown v3 : 8.8
First Time		Exim exim Libspf2 Project Exim Libspf2 Project libspf2

28 Mar 2025, 12:15

Type	Values Removed	Values Added
References		() http://www.openwall.com/lists/oss-security/2025/03/28/1 -

Information

Published : 2024-05-03 03:15

Updated : 2025-08-07 18:17

NVD link : CVE-2023-42118

Mitre link : CVE-2023-42118

CVE.ORG link : CVE-2023-42118

JSON object : View

Products Affected

exim

exim

libspf2_project

libspf2

CWE

CWE-191

Integer Underflow (Wrap or Wraparound)

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