Name: CVE-2026-40685: Incorrect Provision of Specified Functionality
Creator: Rapid7
Published: 2026-04-30T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2026-40685, CWE-684, CWE-787, CVSS 6.5, EPSS 0.00575

In Exim before 4.99.2, when JSON lookup is enabled, an out-of-bounds heap write can occur when a JSON operator encounters malformed JSON in an untrusted header, because of an incorrect implementation of \ skipping.

CVSS Details

CVSS 3.1 Base Score: 6.5
CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Alpine Linux	—	Upgrade exim	May 4, 2026	Apr 30, 2026
Debian	—	Upgrade exim4	May 13, 2026	May 13, 2026
Exim	—	Upgrade Exim to version 4.99.2	Jun 9, 2026	Apr 30, 2026
Gentoo Linux	—	Upgrade mail-mta/exim.	Aug 16, 2026	Aug 14, 2026
Ubuntu	—	Upgrade exim4-baseUpgrade eximon4 (Ubuntu Pro)Upgrade exim4Upgrade eximon4Upgrade exim4-dev (Ubuntu Pro)Upgrade exim4-daemon-heavy (Ubuntu Pro)Upgrade exim4-daemon-light (Ubuntu Pro)Upgrade exim4-base (Ubuntu Pro)Upgrade exim4 (Ubuntu Pro)	May 4, 2026	Apr 29, 2026

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CVSS Details

Covered by Rapid7

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