CVE-2025-4476 · cross-distro fix matrix

CVE-2025-4476: A denial-of-service vulnerability has been identified in the libsoup HTTP client library. This flaw can be triggered when a libsoup client receives a 401 (Unauthorized) HTTP response containing a specifically crafted domain parameter within the WWW-Authenticate header. Processing this malformed head

Affects 2 Linux releases across 2 (distro × package) combinations.

Fix per ecosystem

Each block below is a distro release where CVE-2025-4476 has a known fix. Run the listed command on that distro to remediate.

Debian bullseye

Source: Debian Security Tracker

libsoup2.4→ fixed in2.72.0-2+deb11u3urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y libsoup2.4
```

Debian trixie

Source: Debian Security Tracker

libsoup3→ fixed in3.6.5-2urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y libsoup3
```

Are YOU affected by CVE-2025-4476?

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

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