Ubuntu USN · USN-8624-1

Sinatra vulnerability

Published: Wed, 29 Jul 2026 19:09

CVE-2025-61921

Summary

Sinatra could be made to crash if it received specially crafted network traffic.

Details

It was discovered that Sinatra did not properly handle header parsing, causing ETag generation to hang when given specific input. A remote attacker could possibly use this issue to cause a denial of service.

Recommended actions per Ubuntu release

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

Ubuntu bionic

ruby-sinatra→1.4.8-1ubuntu0.1~esm3apt_upgrade_esm
Fixed at 1.4.8-1ubuntu0.1~esm3 — ESM-only. Enable Ubuntu Pro (free for 5 personal machines) or treat as watch item.
```
sudo pro attach <token>
sudo apt-get update
sudo apt-get install --only-upgrade -y ruby-sinatra=1.4.8-1ubuntu0.1~esm3
```
Sign up at https://ubuntu.com/pro. Free for personal + small-team use.
ruby-sinatra→1.4.8-1ubuntu0.1~esm3apt_upgrade_esm
Fixed at 1.4.8-1ubuntu0.1~esm3 — ESM-only. Enable Ubuntu Pro (free for 5 personal machines) or treat as watch item.
```
sudo pro attach <token>
sudo apt-get update
sudo apt-get install --only-upgrade -y ruby-sinatra=1.4.8-1ubuntu0.1~esm3
```
Sign up at https://ubuntu.com/pro. Free for personal + small-team use.

Ubuntu focal

ruby-sinatra→2.0.8.1-1ubuntu0.1~esm3apt_upgrade_esm
Fixed at 2.0.8.1-1ubuntu0.1~esm3 — ESM-only. Enable Ubuntu Pro (free for 5 personal machines) or treat as watch item.
```
sudo pro attach <token>
sudo apt-get update
sudo apt-get install --only-upgrade -y ruby-sinatra=2.0.8.1-1ubuntu0.1~esm3
```
Sign up at https://ubuntu.com/pro. Free for personal + small-team use.
ruby-rack-protection→2.0.8.1-1ubuntu0.1~esm3apt_upgrade_esm
Fixed at 2.0.8.1-1ubuntu0.1~esm3 — ESM-only. Enable Ubuntu Pro (free for 5 personal machines) or treat as watch item.
```
sudo pro attach <token>
sudo apt-get update
sudo apt-get install --only-upgrade -y ruby-rack-protection=2.0.8.1-1ubuntu0.1~esm3
```
Sign up at https://ubuntu.com/pro. Free for personal + small-team use.
ruby-sinatra→2.0.8.1-1ubuntu0.1~esm3apt_upgrade_esm
Fixed at 2.0.8.1-1ubuntu0.1~esm3 — ESM-only. Enable Ubuntu Pro (free for 5 personal machines) or treat as watch item.
```
sudo pro attach <token>
sudo apt-get update
sudo apt-get install --only-upgrade -y ruby-sinatra=2.0.8.1-1ubuntu0.1~esm3
```
Sign up at https://ubuntu.com/pro. Free for personal + small-team use.
ruby-sinatra-contrib→2.0.8.1-1ubuntu0.1~esm3apt_upgrade_esm
Fixed at 2.0.8.1-1ubuntu0.1~esm3 — ESM-only. Enable Ubuntu Pro (free for 5 personal machines) or treat as watch item.
```
sudo pro attach <token>
sudo apt-get update
sudo apt-get install --only-upgrade -y ruby-sinatra-contrib=2.0.8.1-1ubuntu0.1~esm3
```
Sign up at https://ubuntu.com/pro. Free for personal + small-team use.

Ubuntu jammy

ruby-sinatra→2.0.8.1-2+deb11u1ubuntu0.1~esm1apt_upgrade_esm
Fixed at 2.0.8.1-2+deb11u1ubuntu0.1~esm1 — ESM-only. Enable Ubuntu Pro (free for 5 personal machines) or treat as watch item.
```
sudo pro attach <token>
sudo apt-get update
sudo apt-get install --only-upgrade -y ruby-sinatra=2.0.8.1-2+deb11u1ubuntu0.1~esm1
```
Sign up at https://ubuntu.com/pro. Free for personal + small-team use.
ruby-rack-protection→2.0.8.1-2+deb11u1ubuntu0.1~esm1apt_upgrade_esm
Fixed at 2.0.8.1-2+deb11u1ubuntu0.1~esm1 — ESM-only. Enable Ubuntu Pro (free for 5 personal machines) or treat as watch item.
```
sudo pro attach <token>
sudo apt-get update
sudo apt-get install --only-upgrade -y ruby-rack-protection=2.0.8.1-2+deb11u1ubuntu0.1~esm1
```
Sign up at https://ubuntu.com/pro. Free for personal + small-team use.
ruby-sinatra→2.0.8.1-2+deb11u1ubuntu0.1~esm1apt_upgrade_esm
Fixed at 2.0.8.1-2+deb11u1ubuntu0.1~esm1 — ESM-only. Enable Ubuntu Pro (free for 5 personal machines) or treat as watch item.
```
sudo pro attach <token>
sudo apt-get update
sudo apt-get install --only-upgrade -y ruby-sinatra=2.0.8.1-2+deb11u1ubuntu0.1~esm1
```
Sign up at https://ubuntu.com/pro. Free for personal + small-team use.
ruby-sinatra-contrib→2.0.8.1-2+deb11u1ubuntu0.1~esm1apt_upgrade_esm
Fixed at 2.0.8.1-2+deb11u1ubuntu0.1~esm1 — ESM-only. Enable Ubuntu Pro (free for 5 personal machines) or treat as watch item.
```
sudo pro attach <token>
sudo apt-get update
sudo apt-get install --only-upgrade -y ruby-sinatra-contrib=2.0.8.1-2+deb11u1ubuntu0.1~esm1
```
Sign up at https://ubuntu.com/pro. Free for personal + small-team use.

Ubuntu xenial

ruby-sinatra→1.4.7-3ubuntu0.1~esm3apt_upgrade_esm
Fixed at 1.4.7-3ubuntu0.1~esm3 — ESM-only. Enable Ubuntu Pro (free for 5 personal machines) or treat as watch item.
```
sudo pro attach <token>
sudo apt-get update
sudo apt-get install --only-upgrade -y ruby-sinatra=1.4.7-3ubuntu0.1~esm3
```
Sign up at https://ubuntu.com/pro. Free for personal + small-team use.
ruby-sinatra→1.4.7-3ubuntu0.1~esm3apt_upgrade_esm
Fixed at 1.4.7-3ubuntu0.1~esm3 — ESM-only. Enable Ubuntu Pro (free for 5 personal machines) or treat as watch item.
```
sudo pro attach <token>
sudo apt-get update
sudo apt-get install --only-upgrade -y ruby-sinatra=1.4.7-3ubuntu0.1~esm3
```
Sign up at https://ubuntu.com/pro. Free for personal + small-team use.

Are YOU affected by USN-8624-1?

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-8624-1 (and any other live CVE) applies. Anonymous, no signup.

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

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