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CWE

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CVE-2026-40687

Published: Apr 30, 2026

Modified: May 1, 2026

PUBLISHED

CVSS v3.1

4.8

MEDIUM

Description

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.

Vendor	Product	Versions
Exim	Exim	affected `0 - < 4.99.2`

Weaknesses (CWE)

CVSS v3.1 Details

CVSS v3.1 Vector

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

Attack Vector

Network

Attack Complexity

High

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

None

Availability

Low

References

https://www.openwall.com/lists/oss-security/2026/04/30/21

https://exim.org/static/doc/security/cve-2026-04.1/CVE2026-40687.assessment

https://code.exim.org/exim/exim/commit/68b963b9f75ca27b38e1c0f8c87037990199f505

https://exim.org/static/doc/security/CVE-2026-40687.txt

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