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CVE-2026-20011

CVE-2026-20011 · Multiple Cisco Products Snort 3 SMTP MIME Denial of Service Vulnerability

This page contains facts from public vulnerability sources. Check the original advisory before updating.

This page shows selected source facts. See the linked advisories for the complete description and affected versions.

Multiple Cisco products are affected by a vulnerability in the Snort 3 SMTP MIME Decoder that could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to restart. This vulnerability is due to a lack of error checking when the MIME fields of the SMTP header are parsed. An attacker could exploit this vulnerability by sending crafted SMTP packets through an established connection to be parsed by Snort 3. A successful exploit could allow the attacker to cause a denial of service (DoS) condition when the Snort 3 Detection Engine unexpectedly restarts.

CVSS 5.8 · Medium · EPSS 0.4%

Published
Updated

Affected products and versions

  • cisco open source snort3

    Versions
    • 3.1.2.0: Affected
    • 3.1.3.0: Affected
    • 3.1.4.0: Affected
    • 3.1.5.0: Affected
    • 3.1.6.0: Affected
    • 3.1.7.0: Affected
    • 3.1.8.0: Affected
    • 3.1.9.0: Affected
    • 3.1.10.0: Affected
    • 3.1.12.0: Affected
    • 3.1.13.0: Affected
    • 3.1.14.0: Affected
    • 3.1.15.0: Affected
    • 3.1.16.0: Affected
    • 3.1.17.0: Affected
    • 3.1.18.0: Affected
    • 3.1.19.0: Affected
    • 3.1.20.0: Affected
    • 3.1.21.0: Affected
    • 3.1.22.0: Affected
    • 3.1.23.0: Affected
    • 3.1.24.0: Affected
    • 3.1.25.0: Affected
    • 3.1.27.0: Affected
    • 3.1.28.0: Affected
    • 3.1.29.0: Affected
    • 3.1.30.0: Affected
    • 3.1.31.0: Affected
    • 3.1.32.0: Affected
    • 3.1.36.0: Affected
    • 3.1.38.0: Affected
    • 3.1.39.0: Affected
    • 3.1.40.0: Affected
    • 3.1.41.0: Affected
    • 3.1.42.0: Affected
    • 3.1.43.0: Affected
    • 3.1.45.0: Affected
    • 3.1.47.0: Affected
    • 3.1.48.0: Affected
    • 3.1.50.0: Affected
    • 3.1.51.0: Affected
    • 3.1.52.0: Affected
    • 3.1.53.0: Affected
    • 3.1.55.0: Affected
    • 3.1.56.0: Affected
    • 3.1.57.0: Affected
    • 3.1.58.0: Affected
    • 3.1.59.0: Affected
    • 3.1.60.0: Affected
    • 3.1.61.0: Affected
    • 3.1.62.0: Affected
    • 3.1.63.0: Affected
    • 3.1.64.0: Affected
    • 3.1.65.0: Affected
    • 3.1.66.0: Affected
    • 3.1.67.0: Affected
    • 3.1.69.0: Affected
    • 3.1.70.0: Affected
    • 3.1.71.0: Affected
    • 3.1.72.0: Affected
    • 3.1.73.0: Affected
    • 3.1.74.0: Affected
    • 3.1.75.0: Affected
    • 3.1.76.0: Affected
    • 3.1.77.0: Affected
    • 3.1.78.0: Affected
    • 3.1.81.0: Affected
    • 3.1.82.0: Affected
    • 3.1.83.0: Affected
    • 3.1.84.0: Affected
    • 3.2.1.0: Affected
    • 3.2.2.0: Affected
    • 3.3.0.0: Affected
    • 3.3.1.0: Affected
    • 3.3.2.0: Affected
    • 3.3.3.0: Affected
    • 3.3.4.0: Affected
    • 3.3.5.0: Affected
    • 3.3.7.0: Affected
    • 3.5.0.0: Affected
    • 3.5.1.0: Affected
    • 3.8.1.0: Affected
    • 3.6.0.0: Affected
    • 3.6.2.0: Affected
    • 3.9.3.0: Affected
    • 3.7.2.0: Affected
    • 3.7.0.0: Affected
    • 3.9.6.0: Affected
    • 3.10.0.0: Affected
    • 3.7.4.0: Affected
    • 3.9.0.0: Affected
    • 3.5.2.0: Affected
    • 3.6.1.0: Affected
    • 3.9.2.0: Affected
    • 3.6.3.0: Affected
    • 3.9.5.0: Affected
    • 3.7.1.0: Affected
    • 3.9.7.0: Affected

    No fix published

  • cisco secure firewall threat defense (ftd) software

    Versions
    • 7.0.0: Affected
    • 7.0.0.1: Affected
    • 7.0.1: Affected
    • 7.0.1.1: Affected
    • 7.0.2: Affected
    • 7.2.0: Affected
    • 7.0.2.1: Affected
    • 7.0.3: Affected
    • 7.2.0.1: Affected
    • 7.0.4: Affected
    • 7.2.1: Affected
    • 7.0.5: Affected
    • 7.3.0: Affected
    • 7.2.2: Affected
    • 7.2.3: Affected
    • 7.3.1: Affected
    • 7.2.4: Affected
    • 7.0.6: Affected
    • 7.2.5: Affected
    • 7.2.4.1: Affected
    • 7.3.1.1: Affected
    • 7.4.0: Affected
    • 7.0.6.1: Affected
    • 7.2.5.1: Affected
    • 7.4.1: Affected
    • 7.2.6: Affected
    • 7.0.6.2: Affected
    • 7.4.1.1: Affected
    • 7.2.7: Affected
    • 7.2.5.2: Affected
    • 7.3.1.2: Affected
    • 7.2.8: Affected
    • 7.6.0: Affected
    • 7.4.2: Affected
    • 7.2.8.1: Affected
    • 7.0.6.3: Affected
    • 7.4.2.1: Affected
    • 7.2.9: Affected
    • 7.0.7: Affected
    • 7.7.0: Affected
    • 7.4.2.2: Affected
    • 7.2.10: Affected
    • 7.6.1: Affected
    • 7.4.2.3: Affected
    • 7.0.8: Affected
    • 7.6.2: Affected
    • 7.7.10: Affected
    • 7.7.11: Affected
    • 7.0.8.1: Affected
    • 7.6.2.1: Affected
    • 7.7.10.1: Affected
    • 7.4.2.4: Affected
    • 7.2.10.2: Affected
    • 7.4.3: Affected
    • 7.6.4: Affected
    • 10.0.0: Affected
    • 7.4.4: Affected
    • 7.0.9: Affected
    • 7.2.11: Affected

    No fix published

  • cisco utd snort ips engine software

    Versions
    • 3.17.1S: Affected
    • 16.12.3: Affected
    • Fuji-16.9.5: Affected
    • 16.12.4: Affected
    • 17.3.1a: Affected
    • 16.6.6: Affected
    • 16.12.2: Affected
    • Fuji-16.9.6: Affected
    • 3.17.0S: Affected
    • Fuji-16.9.3: Affected
    • Denali-16.3.7: Affected
    • Fuji-16.9.2: Affected
    • Fuji-16.9.4: Affected
    • Everest-16.6.4: Affected
    • Everest-16.6.3: Affected
    • 16.6.5: Affected
    • Denali-16.3.5: Affected
    • 17.2.1r: Affected
    • 17.1.1: Affected
    • Everest-16.6.2: Affected
    • 16.6.7a: Affected
    • Denali-16.3.4: Affected
    • 16.6.1: Affected
    • Denali-16.3.9: Affected
    • Denali-16.3.3: Affected
    • 16.12.1a: Affected
    • 17.3.2: Affected
    • 17.4.1a: Affected
    • 16.12.5: Affected
    • Fuji-16.9.7: Affected
    • 16.6.9: Affected
    • 17.3.3: Affected
    • 17.5.1a: Affected
    • 17.3.4a: Affected
    • 17.4.2: Affected
    • 17.4.1b: Affected
    • 17.6.1a: Affected
    • 16.6.10: Affected
    • 17.7.1a: Affected
    • 16.12.6: Affected
    • Fuji-16.9.8: Affected
    • 17.6.2: Affected
    • 17.8.1a: Affected
    • 16.12.7: Affected
    • 17.3.5: Affected
    • 17.6.3a: Affected
    • 17.7.2: Affected
    • 17.9.1a: Affected
    • 17.6.4: Affected
    • 17.10.1a: Affected
    • 17.3.6: Affected
    • 16.12.8: Affected
    • 17.3.7: Affected
    • 17.9.2a: Affected
    • 17.6.5: Affected
    • 17.11.1a: Affected
    • 17.9.3a: Affected
    • 17.12.1a: Affected
    • 17.9.4: Affected
    • 17.6.6: Affected
    • 17.3.8: Affected
    • 17.12.2: Affected
    • 17.13.1a: Affected
    • 17.9.5a: Affected
    • 17.12.3: Affected
    • 17.6.7: Affected
    • 17.14.1a: Affected
    • 17.12.4: Affected
    • 17.12.3a: Affected
    • 17.15.1a: Affected
    • 17.9.6: Affected
    • 17.6.8a: Affected
    • 17.16.1a: Affected
    • 17.9.5e: Affected
    • 17.12.4a: Affected
    • 17.15.2c: Affected
    • 17.9.5f: Affected
    • 17.12.4b: Affected
    • 17.15.2a: Affected
    • 17.12.5: Affected
    • 17.17.1: Affected
    • 17.12.5a: Affected
    • 17.9.7a: Affected
    • 17.15.3a: Affected
    • 17.15.3: Affected
    • 17.12.5b: Affected
    • 17.12.5c: Affected
    • 17.15.4: Affected
    • 17.9.7b: Affected
    • 17.18.1: Affected
    • 17.18.1a: Affected
    • 17.12.6: Affected
    • 17.9.8: Affected
    • 17.15.4c: Affected
    • 17.12.5d: Affected
    • 17.18.2: Affected
    • 26.1.1: Affected
    • 17.15.5: Affected

    No fix published

Original sources

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