PatchTheCVECVE-2006-6931: Algorithmic complexity vulnerability in Snort before 2.6.1, during predicate evaluation in rule matching for c
CVE-2006-6931 is a medium-severity flaw (CVSS 5.0) affecting snort. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
Algorithmic complexity vulnerability in Snort before 2.6.1, during predicate evaluation in rule matching for certain rules, allows remote attackers to cause a denial of service (CPU consumption and detection outage) via crafted network traffic, aka a "backtracking attack."
Why this priority
- No elevated risk signals yet
A fixed release or distro patch exists.
Risk facts
| CVSS score | 5.0 (Medium) |
| EPSS exploit chance | 2.4% (top 16%) |
| CISA exploited list | No |
| Published | 2007-01-16 |
| Last modified | 2026-06-16 |
Last updated 2026-06-16 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2006-6931?
snort: upgrade to newer than 2.6.2. Exact commands for each OS are on this page.
Is CVE-2006-6931 being exploited?
CVE-2006-6931 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2006-6931 affect?
CVE-2006-6931 affects snort. Severity is medium (CVSS 5.0). Algorithmic complexity vulnerability in Snort before 2.6.1, during predicate evaluation in rule matching for certain rules, allows remote attackers to cause a denial of service (CPU consumption and detection outage) via crafted network traf
How urgent is CVE-2006-6931?
Priority 39/100. No elevated risk signals yet.
Software pages
Suricata and Snort vulnerabilities
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