CVE-2007-4321 describes a denial-of-service vulnerability in Fail2ban versions 0.8 and earlier, where improper parsing of sshd log files allows remote attackers to add arbitrary hosts to /etc/hosts.deny. This is achieved by injecting IP address strings into the sshd log via a crafted SSH client protocol version identification. The vulnerability carries a CVSS score of 6.8, indicating a medium severity with network access, medium attack complexity, and potential for partial confidentiality, integrity, and availability impact. While not actively exploited in the wild (no KEV entry), public exploit code exists on ExploitDB, and the CVE has garnered significant community discussion, suggesting awareness among security researchers.
| Vendor | Product | Version(s) | CPE |
|---|---|---|---|
0.8CPE matchmatch criteria | cpe:2.3:a:fail2ban:fail2ban:0.8:*:*:*:*:*:*:* |
CVSS version used by this source: 2.0
AV:N/AC:M/Au:N/C:P/I:P/A:P
The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.0 Bluesky, 0.0 Mastodon, and 0.2 GitHub mentions.
No media coverage found for this CVE.
The average CVE in this peer group has 0.0 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.
Remediation records are not available for this CVE.