CVE-2025-6021 · cross-distro fix matrix

CVE-2025-6021: A flaw was found in libxml2's xmlBuildQName function, where integer overflows in buffer size calculations can lead to a stack-based buffer overflow. This issue can result in memory corruption or a denial of service when processing crafted input.

Affects 5 Linux releases across 5 (distro × package) combinations.

Fix per ecosystem

Each block below is a distro release where CVE-2025-6021 has a known fix. Run the listed command on that distro to remediate.

Debian bullseye

Source: Debian Security Tracker

libxml2→ fixed in2.9.10+dfsg-6.7+deb11u8urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y libxml2
```

Debian bookworm

Source: Debian Security Tracker

libxml2→ fixed in2.9.14+dfsg-1.3~deb12u3urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y libxml2
```

Debian trixie

Source: Debian Security Tracker

libxml2→ fixed in2.12.7+dfsg+really2.9.14-2urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y libxml2
```

Alpine v3.21

Source: Alpine secdb

libxml2→ fixed in2.13.9-r0
```
apk update && apk add --upgrade libxml2
```

Alpine edge

Source: Alpine secdb

libxml2→ fixed in2.13.9-r0
```
apk update && apk add --upgrade libxml2
```

Are YOU affected by CVE-2025-6021?

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

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