CVE-2026-66141: Exim: Exim before 4.99.5 allows .forward privilege escalation because force_command for a pipe t…

High 7.8 EPSS 0.1% Exim

Exim before 4.99.5 allows .forward privilege escalation because force_command for a pipe transport is mishandled.

• CVE-2026-66141CVE identifier
• 7.8CVSS 3.1 base score (high)
• 0.1%EPSS: chance of exploitation in the next 30 days (higher than 3% of CVEs)
• 2026-07-24published

What do these terms mean? CVE · CVSS score · exploited (KEV) · EPSS · backported fix · all terms

Affected and fixed versions

Affected:

• Exim Exim 4.82 to before 4.99.5

Patch it

Use the commands for your system. Distribution packages often keep an older version number with the fix backported, so compare with the fixed package versions in the table below, not only with the upstream version.

sudo apt update
sudo apt install --only-upgrade exim4-daemon-light (or exim4-daemon-heavy)

sudo apt update
sudo apt install --only-upgrade exim4-daemon-light (or exim4-daemon-heavy)

sudo dnf upgrade --refresh exim (EPEL)

sudo dnf upgrade --refresh exim

sudo zypper refresh
sudo zypper update exim

not in distro repos: vendor repository

sudo pacman -Syu

apk update && apk upgrade exim

pkg update && pkg upgrade exim

General update steps for every system are on the Linux and Unix & BSD pages; after updating, see which services to restart.

Fix status in Linux distributions

From the Debian security tracker, Ubuntu CVE tracker and Red Hat Security Data API, refreshed every few hours.

Sources

• https://openwall.com/lists/oss-security/2026/07/22/9
• CVE-2026-66141 on CVE.org
• CVE-2026-66141 on NVD

Page generated automatically from official sources on 2026-11-03 18:05 UTC. Always confirm with your vendor's advisory.