CVE-2026-33721 · cross-distro fix matrix

CVE-2026-33721: MapServer is a system for developing web-based GIS applications. Starting in version 4.2 and prior to version 8.6.1, a heap-buffer-overflow write in MapServer’s SLD (Styled Layer Descriptor) parser lets a remote, unauthenticated attacker crash the MapServer process by sending a crafted SLD with more

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

Fix per ecosystem

Each block below is a distro release where CVE-2026-33721 has a known fix. Run the listed command on that distro to remediate.

Debian bullseye

Source: Debian Security Tracker

mapserver→ fixed in7.6.2-1+deb11u2urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y mapserver
```

Are YOU affected by CVE-2026-33721?

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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