Ubuntu USN · USN-8353-1

Exim vulnerability

Published: Mon, 01 Jun 2026 13:24

CVE-2026-48840

Summary

Exim could be made to expose sensitive information over the network.

Details

Warisjeet Singh discovered that Exim with SUPPORT_PROXY enabled did not properly handle memory before SMTP authentication. A remote attacker could possibly use this issue to obtain sensitive information.

Recommended actions per Ubuntu release

StackPatch playbook auto-generated per release codename and per affected package.

Ubuntu jammy

exim4→4.95-4ubuntu2.9apt_upgrade
Standard apt upgrade. Install 4.95-4ubuntu2.9 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y exim4
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
exim4→4.95-4ubuntu2.9apt_upgrade
Standard apt upgrade. Install 4.95-4ubuntu2.9 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y exim4
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
exim4-base→4.95-4ubuntu2.9apt_upgrade
Standard apt upgrade. Install 4.95-4ubuntu2.9 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y exim4-base
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
exim4-config→4.95-4ubuntu2.9apt_upgrade
Standard apt upgrade. Install 4.95-4ubuntu2.9 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y exim4-config
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
exim4-daemon-heavy→4.95-4ubuntu2.9apt_upgrade
Standard apt upgrade. Install 4.95-4ubuntu2.9 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y exim4-daemon-heavy
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
exim4-daemon-light→4.95-4ubuntu2.9apt_upgrade
Standard apt upgrade. Install 4.95-4ubuntu2.9 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y exim4-daemon-light
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
exim4-dev→4.95-4ubuntu2.9apt_upgrade
Standard apt upgrade. Install 4.95-4ubuntu2.9 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y exim4-dev
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
eximon4→4.95-4ubuntu2.9apt_upgrade
Standard apt upgrade. Install 4.95-4ubuntu2.9 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y eximon4
```
Most apt upgrades restart their service automatically. needrestart lists anything else.

Ubuntu noble

exim4→4.97-4ubuntu4.6apt_upgrade
Standard apt upgrade. Install 4.97-4ubuntu4.6 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y exim4
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
exim4→4.97-4ubuntu4.6apt_upgrade
Standard apt upgrade. Install 4.97-4ubuntu4.6 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y exim4
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
exim4-base→4.97-4ubuntu4.6apt_upgrade
Standard apt upgrade. Install 4.97-4ubuntu4.6 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y exim4-base
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
exim4-config→4.97-4ubuntu4.6apt_upgrade
Standard apt upgrade. Install 4.97-4ubuntu4.6 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y exim4-config
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
exim4-daemon-heavy→4.97-4ubuntu4.6apt_upgrade
Standard apt upgrade. Install 4.97-4ubuntu4.6 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y exim4-daemon-heavy
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
exim4-daemon-light→4.97-4ubuntu4.6apt_upgrade
Standard apt upgrade. Install 4.97-4ubuntu4.6 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y exim4-daemon-light
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
exim4-dev→4.97-4ubuntu4.6apt_upgrade
Standard apt upgrade. Install 4.97-4ubuntu4.6 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y exim4-dev
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
eximon4→4.97-4ubuntu4.6apt_upgrade
Standard apt upgrade. Install 4.97-4ubuntu4.6 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y eximon4
```
Most apt upgrades restart their service automatically. needrestart lists anything else.

Ubuntu questing

exim4→4.98.2-1ubuntu2.3apt_upgrade
Standard apt upgrade. Install 4.98.2-1ubuntu2.3 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y exim4
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
exim4→4.98.2-1ubuntu2.3apt_upgrade
Standard apt upgrade. Install 4.98.2-1ubuntu2.3 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y exim4
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
exim4-base→4.98.2-1ubuntu2.3apt_upgrade
Standard apt upgrade. Install 4.98.2-1ubuntu2.3 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y exim4-base
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
exim4-config→4.98.2-1ubuntu2.3apt_upgrade
Standard apt upgrade. Install 4.98.2-1ubuntu2.3 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y exim4-config
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
exim4-daemon-heavy→4.98.2-1ubuntu2.3apt_upgrade
Standard apt upgrade. Install 4.98.2-1ubuntu2.3 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y exim4-daemon-heavy
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
exim4-daemon-light→4.98.2-1ubuntu2.3apt_upgrade
Standard apt upgrade. Install 4.98.2-1ubuntu2.3 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y exim4-daemon-light
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
exim4-dev→4.98.2-1ubuntu2.3apt_upgrade
Standard apt upgrade. Install 4.98.2-1ubuntu2.3 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y exim4-dev
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
eximon4→4.98.2-1ubuntu2.3apt_upgrade
Standard apt upgrade. Install 4.98.2-1ubuntu2.3 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y eximon4
```
Most apt upgrades restart their service automatically. needrestart lists anything else.

Ubuntu resolute

exim4→4.99.1-1ubuntu1.3apt_upgrade
Standard apt upgrade. Install 4.99.1-1ubuntu1.3 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y exim4
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
exim4→4.99.1-1ubuntu1.3apt_upgrade
Standard apt upgrade. Install 4.99.1-1ubuntu1.3 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y exim4
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
exim4-base→4.99.1-1ubuntu1.3apt_upgrade
Standard apt upgrade. Install 4.99.1-1ubuntu1.3 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y exim4-base
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
exim4-config→4.99.1-1ubuntu1.3apt_upgrade
Standard apt upgrade. Install 4.99.1-1ubuntu1.3 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y exim4-config
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
exim4-daemon-heavy→4.99.1-1ubuntu1.3apt_upgrade
Standard apt upgrade. Install 4.99.1-1ubuntu1.3 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y exim4-daemon-heavy
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
exim4-daemon-light→4.99.1-1ubuntu1.3apt_upgrade
Standard apt upgrade. Install 4.99.1-1ubuntu1.3 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y exim4-daemon-light
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
exim4-dev→4.99.1-1ubuntu1.3apt_upgrade
Standard apt upgrade. Install 4.99.1-1ubuntu1.3 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y exim4-dev
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
eximon4→4.99.1-1ubuntu1.3apt_upgrade
Standard apt upgrade. Install 4.99.1-1ubuntu1.3 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y eximon4
```
Most apt upgrades restart their service automatically. needrestart lists anything else.

Are YOU affected by USN-8353-1?

5-second check on your actual server. Reads /etc/os-release, uname -r, and dpkg-query; matches against the live USN + Debian Security Tracker feeds; tells you whether USN-8353-1 (and any other live CVE) applies. Anonymous, no signup.

curl https://mindsparkstack.com/scan.sh | bash

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