|
Vulnerabilities
< Back

CVE-2026-40685

Updated on 30 Apr 2026

Severity

9.8 Critical severity

Details

CVSS score
9.8
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE ID
Links
NISTCIRCLRHELUbuntu

Overview

About vulnerability

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.

Details

Affected product:
AlmaLinux 9.2 ESU , Alpine Linux 3.18 ELS , CentOS 6 ELS , CentOS 7 ELS , CentOS 8.4 ELS , CentOS 8.5 ELS , Oracle Linux 6 ELS , TuxCare 9.6 ESU , Ubuntu 16.04 ELS , Ubuntu 18.04 ELS , Ubuntu 20.04 ELS
Affected packages:
exim @ 4.99.1 (+11 more)
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.

Fixes