Ubuntu USN · USN-6455-2

Exim regression

Published: Wed, 10 Jun 2026 12:22

Summary

USN-6455-1 introduced a regression in Exim

Details

USN-6455-1 fixed vulnerabilities in Exim. The fix for CVE-2023-42117 introduced a regression on Ubuntu 22.04 LTS that resulted in certain connections logging a Taint mismatch error. This update fixes the problem. We apologize for the inconvenience. Original advisory details: It was discovered that Exim incorrectly handled validation of user-supplied data, which could lead to memory corruption. A remote attacker could possibly use this issue to execute arbitrary code. (CVE-2023-42117) It was discovered that Exim incorrectly handled validation of user-supplied data, which could lead to an out-of-bounds read. An attacker could possibly use this issue to expose sensitive information. (CVE-2023-42119)

Recommended actions per Ubuntu release

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

Ubuntu jammy

exim4→4.95-4ubuntu2.10apt_upgrade
Standard apt upgrade. Install 4.95-4ubuntu2.10 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→4.95-4ubuntu2.10apt_upgrade
Standard apt upgrade. Install 4.95-4ubuntu2.10 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→4.95-4ubuntu2.10apt_upgrade
Standard apt upgrade. Install 4.95-4ubuntu2.10 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→4.95-4ubuntu2.10apt_upgrade
Standard apt upgrade. Install 4.95-4ubuntu2.10 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→4.95-4ubuntu2.10apt_upgrade
Standard apt upgrade. Install 4.95-4ubuntu2.10 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→4.95-4ubuntu2.10apt_upgrade
Standard apt upgrade. Install 4.95-4ubuntu2.10 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→4.95-4ubuntu2.10apt_upgrade
Standard apt upgrade. Install 4.95-4ubuntu2.10 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→4.95-4ubuntu2.10apt_upgrade
Standard apt upgrade. Install 4.95-4ubuntu2.10 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-6455-2?

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

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References

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