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TI-2019-01600 Aliases CVE-2019-1981GHSA-55w6-hghf-mfpw

Cisco Firepower Threat Defense Software NULL Character Obfuscation Detection Bypass Vulnerability

Priority LOW 34CWE-264Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
None · Low · None
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-264.

Summary

A vulnerability in the normalization functionality of Cisco Firepower Threat Defense Software, Cisco FirePOWER Services Software for ASA, and Cisco Firepower Management Center Software could allow an unauthenticated, remote attacker to bypass filtering protections. The vulnerability is due to insufficient normalization of a text-based payload. An attacker could exploit this vulnerability by sending traffic that contains specifically obfuscated payloads through an affected device. An exploit could allow the attacker to bypass filtering and deliver malicious payloads to protected systems that would otherwise be blocked.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.01042 64th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
CiscoCisco Firepower Threat Defense Softwareall versions—No fix listedCNA
  • Cisco Firepower Threat Defense Software VendorCisco Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 5

CPEVersionsRoleVendor
cpe:2.3:a:cisco:firepower_services_software_for_asa:*:*:*:*:*:*:*:*all versionsVulnerableCisco
cpe:2.3:a:cisco:secure_firewall_management_center:*:*:*:*:*:*:*:*2.9.12 – 2.9.12.15; 2.9.13 – 2.9.13.6; 2.9.14.0 – 2.9.14.5VulnerableCisco
cpe:2.3:a:cisco:secure_firewall_management_center:2.9.15:*:*:*:*:*:*:*2.9.15VulnerableCisco
cpe:2.3:a:cisco:secure_firewall_management_center:2.9.16:*:*:*:*:*:*:*2.9.16VulnerableCisco
cpe:2.3:a:cisco:secure_firewall_threat_defense:*:*:*:*:*:*:*:*all versionsVulnerableCisco
  • cpe:2.3:a:cisco:firepower_services_software_for_asa:*:*:*:*:*:*:*:* Versions all versions Vulnerable ·Cisco
  • cpe:2.3:a:cisco:secure_firewall_management_center:*:*:*:*:*:*:*:* Versions 2.9.12 – 2.9.12.15; 2.9.13 – 2.9.13.6; 2.9.14.0 – 2.9.14.5 Vulnerable ·Cisco
  • cpe:2.3:a:cisco:secure_firewall_management_center:2.9.15:*:*:*:*:*:*:* Versions 2.9.15 Vulnerable ·Cisco
  • cpe:2.3:a:cisco:secure_firewall_management_center:2.9.16:*:*:*:*:*:*:* Versions 2.9.16 Vulnerable ·Cisco
  • cpe:2.3:a:cisco:secure_firewall_threat_defense:*:*:*:*:*:*:*:* Versions all versions Vulnerable ·Cisco

Remediation

No fixed version listed by the sources yet.

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    Cisco Firepower Threat Defense Software n/a

    3 records Highest priority Priority MEDIUM 1 MEDIUM, 2 LOW

    Other records, highest priority first

    • TI-2019-01598 Cisco Firepower Threat Defense Software Stream Reassembly Bypass VulnerabilityPriority MEDIUM 44
    • TI-2019-01599 Cisco Firepower Threat Defense Software Nonstandard Protocol Detection Bypass VulnerabilityPriority LOW 32
    Show all 3 records →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2019-1981
  2. 2026-10-03 Alias added: GHSA-55w6-hghf-mfpw

References

Advisory 1

  • TI-2019-01598 Cisco Firepower Threat Defense Software Stream Reassembly Bypass Vulnerability CVSS 3.1MEDIUM 5.8
  • TI-2022-05477 Improper access control in Cisco Firepower Management Center CVSS 3.1HIGH 7.5
  • TI-2022-05486 Buffer overflow in Cisco Adaptive Security Appliance Software CVSS 3.1HIGH 7.7
  • TI-2019-01601 Cisco Firepower Threat Defense Software HTTP Filtering Bypass Vulnerability CVSS 3.1MEDIUM 5.3
  • TI-2019-01599 Cisco Firepower Threat Defense Software Nonstandard Protocol Detection Bypass Vulnerability CVSS 3.1MEDIUM 5.3

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences