Cisco Snort Community Rules

Use in your agent

Load Snort Community Rules into pandas and Parquet. Checked against the provider's documentation on Nov 1, 2026.

Access

• No account or key. The Snort 3 Community Rules tar.gz archive is a public download.

Request

curl -L -O 'https://www.snort.org/downloads/community/snort3-community-rules.tar.gz'

Format

A gzip-compressed tar archive containing one Snort 3 rules text file, a SID-message map, authors and licence files. Active rule lines include an action, network direction and semicolon-delimited options such as msg, content, classtype, reference, sid and rev.

Load into pandas and Parquet

Needs Python 3 with requests, pandas and pyarrow.

"""Snort 3 Community Rules -> pandas -> Parquet. No key."""
import io
import re
import tarfile

import pandas as pd
import requests

URL = "https://www.snort.org/downloads/community/snort3-community-rules.tar.gz"
r = requests.get(URL, timeout=60)
r.raise_for_status()
with tarfile.open(fileobj=io.BytesIO(r.content), mode="r:gz") as archive:
    member = next(m for m in archive.getmembers() if m.name.endswith(".rules"))
    text = archive.extractfile(member).read().decode("utf-8", errors="replace")

rows = []
for line in text.splitlines():
    if not re.match(r"^(alert|block|drop|pass|reject|sdrop)\s", line):
        continue
    def field(name):
        match = re.search(rf"(?:^|;)\s*{name}:\s*([^;]+)", line)
        return match.group(1).strip().strip('\"') if match else None
    rows.append({"action": line.split(None, 1)[0], "sid": field("sid"),
                 "rev": field("rev"), "message": field("msg"),
                 "class_type": field("classtype")})

df = pd.DataFrame(rows)
df[["sid", "rev"]] = df[["sid", "rev"]].apply(pd.to_numeric, errors="coerce")
df.to_parquet("snort_community_rules.parquet", index=False)
print(len(df), "active rules", df["class_type"].nunique(), "classification types",
      "SID range", int(df["sid"].min()), "to", int(df["sid"].max()))

Run by us on 2026-11-01 (python 3.13.5 | pandas 3.1.0 | pyarrow 26.0.0 | requests 2.34.2). Result: 4024 active rules 27 classification types SID range 105 to 300307

Limits

• Rate limit: Not stated.
• No publication schedule or download cap is stated for Community Rules.
• The download is a current bundle, not a historical rule archive.

Quirks

• The parser indexes active rule lines and skips comments or disabled rules.
• A rule match is not proof of compromise; tune variables, enabled state and thresholds for the monitored network.
• Rule references or content can contain malicious destinations or indicators. Do not visit or fetch them.

Terms and attribution

• Community Rules are separately available under GNU GPL version 2.
• Keep applicable copyright, warranty and licence notices when redistributing the rules.

Sources

• https://www.snort.org/downloads#rules: “Download the latest Snort open source network intrusion prevention software. Review the list of free and paid Snort rules to properly manage the software.”
• https://www.snort.org/rules_explanation: “This category contains URI, USER-AGENT, DNS, and IP address rules that have been determined to be indicators of malicious activity.”
• https://www.snort.org/downloads/community/snort3-community-rules.tar.gz: “Community Rules. The Community Rules are not governed by this Agreement and”