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Known Affected Software Configurations Switch to CPE 2.2

Change History

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

CWE-787

OR
          *cpe:2.3:a:exim:exim:*:*:*:*:*:*:*:* versions up to (excluding) 4.99.2

MITRE: https://code.exim.org/exim/exim/commit/9fdc057e71b87c87a0d3d2288b2810a0efaaba57 Types: Patch

MITRE: https://exim.org/static/doc/security/CVE-2026-40685.txt Types: Broken Link

MITRE: https://exim.org/static/doc/security/cve-2026-04.1/CVE2026-40685.assessment Types: Vendor Advisory

MITRE: https://www.openwall.com/lists/oss-security/2026/04/30/21 Types: Mailing List, Third Party Advisory

https://exim.org/static/doc/security/CVE-2026-40685.txt

https://exim.org/static/doc/security/CVE-2025-40685.txt

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.

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

CWE-684

https://code.exim.org/exim/exim/commit/9fdc057e71b87c87a0d3d2288b2810a0efaaba57

https://exim.org/static/doc/security/CVE-2025-40685.txt

https://exim.org/static/doc/security/cve-2026-04.1/CVE2026-40685.assessment

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