CVE-2009-5023 · cross-distro fix matrix

CVE-2009-5023: The (1) dshield.conf, (2) mail-buffered.conf, (3) mynetwatchman.conf, and (4) mynetwatchman.conf actions in action.d/ in Fail2ban before 0.8.5 allows local users to write to arbitrary files via a symlink attack on temporary files with predictable names, as demonstrated by /tmp/fail2ban-mail.txt.

Affects 3 Linux releases across 3 (distro × package) combinations.

Fix per ecosystem

Each block below is a distro release where CVE-2009-5023 has a known fix. Run the listed command on that distro to remediate.

Debian bullseye

Source: Debian Security Tracker

fail2ban→ fixed in0.8.4+svn20110323-1urgency: low
```
sudo apt-get install --only-upgrade -y fail2ban
```

Debian bookworm

Source: Debian Security Tracker

fail2ban→ fixed in0.8.4+svn20110323-1urgency: low
```
sudo apt-get install --only-upgrade -y fail2ban
```

Debian trixie

Source: Debian Security Tracker

fail2ban→ fixed in0.8.4+svn20110323-1urgency: low
```
sudo apt-get install --only-upgrade -y fail2ban
```

Are YOU affected by CVE-2009-5023?

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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