CVE-2025-61921 · cross-distro fix matrix

CVE-2025-61921: Sinatra is a domain-specific language for creating web applications in Ruby. In versions prior to 4.2.0, there is a denial of service vulnerability in the `If-Match` and `If-None-Match` header parsing component of Sinatra, if the `etag` method is used when constructing the response. Carefully crafte

Affects 1 Linux release across 1 (distro × package) combinations.

Fix per ecosystem

Each block below is a distro release where CVE-2025-61921 has a known fix. Run the listed command on that distro to remediate.

Debian bookworm

Source: Debian Security Tracker

ruby-sinatra→ fixed in3.0.5-3+deb12u1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y ruby-sinatra
```

Are YOU affected by CVE-2025-61921?

5-second check on your actual server. Reads /etc/os-release, uname -r, and the distro's package manager; matches against this same cross-source index live.

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

Form-based quickscan View on NVD

Continuous monitoring beats manual checking

CVE-2025-61921dropped silently in your distro's update channel. Every new CVE is the same story. StackPatch runs the matcher hourly against all 5 sources and emails the exact remediation when something new applies to one of your servers. $99 lifetime, 50 founder seats, 30-day refund.

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