CVE-2025-67896

Exim before 4.99.1, with certain non-default rate-limit configurations, allows a remote heap-based buffer overflow because database records are cast directly to internal structures without validation.

CVSS v3 7.0 HIGH

7.0^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 4.7

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact HIGH

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://exim.org/static/doc/security/	Vendor Advisory
https://exim.org/static/doc/security/EXIM-Security-2025-12-09.1/report.txt	Vendor Advisory
https://www.openwall.com/lists/oss-security/2025/12/11/2	Mailing List
http://www.openwall.com/lists/oss-security/2025/12/14/1	Mailing List
http://www.openwall.com/lists/oss-security/2025/12/18/3	Mailing List

Configurations

Configuration 1 (hide)

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

History

14 Oct 2026, 13:10

Type	Values Removed	Values Added
Summary		(es) Exim anterior a 4.99.1, con ciertas configuraciones de límite de tasa no predeterminadas, permite un desbordamiento de búfer basado en montículo remoto porque los registros de la base de datos se convierten directamente a estructuras internas sin validación.

Information

Published : 2025-12-14 04:15

Updated : 2026-10-14 13:10

NVD link : CVE-2025-67896

Mitre link : CVE-2025-67896

CVE.ORG link : CVE-2025-67896

JSON object : View

Products Affected

exim

exim

CWE

CWE-122

Heap-based Buffer Overflow

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