CVE-2026-40687

In Exim before 4.99.2, when the SPA authentication driver is used with an adversarial SPA resource, there can be an out-of-bounds write that crashes the connection instance, or erroneous data processing that divulges data from uninitialized heap memory.

CVSS v3 4.8 MEDIUM

4.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://code.exim.org/exim/exim/commit/68b963b9f75ca27b38e1c0f8c87037990199f505	Patch
https://exim.org/static/doc/security/CVE-2026-40687.txt	Broken Link
https://exim.org/static/doc/security/cve-2026-04.1/CVE2026-40687.assessment	Vendor Advisory
https://www.openwall.com/lists/oss-security/2026/04/30/21	Mailing List Third Party Advisory

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-04-30 22:16

Updated : 2026-06-17 10:45

NVD link : CVE-2026-40687

Mitre link : CVE-2026-40687

CVE.ORG link : CVE-2026-40687

JSON object : View

Products Affected

exim

exim

CWE

CWE-909

Missing Initialization of Resource

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