CVE-2026-40686 LOW

CVE-2026-40686

Vendor Exim
Product Exim
Weakness CWE-125
Published April 30, 2026
Last update May 1, 2026

CVSS base score

3.7/10
Attack vector Network
Attack complexity High
Privileges required None
User interaction None
Confidentiality Low
Integrity None

CVSS vector

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

What the vulnerability does

01Description

In Exim before 4.99.2, when utf8 operators are enabled, there is an out-of-bounds read if large UTF-8 trailing characters are present (malformed UTF-8 header data). Information might be divulged within an error message produced during handling of an unrelated e-mail message.

Key dates

02Disclosure timeline

April 30, 2026 CVE published
May 1, 2026 Record updated