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TI-2020-03099 Aliases CVE-2020-3555GHSA-r7x6-g4f2-fq99

Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software SIP Denial of Service Vulnerability

Priority LOW 36CWE-404Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-404.

Summary

A vulnerability in the SIP inspection process of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a crash and reload of an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to a watchdog timeout and crash during the cleanup of threads that are associated with a SIP connection that is being deleted from the connection list. An attacker could exploit this vulnerability by sending a high rate of crafted SIP traffic through an affected device. A successful exploit could allow the attacker to cause a watchdog timeout and crash, resulting in a crash and reload of the affected device.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.01696 77th 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
No
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 Adaptive Security Appliance (ASA) Softwareall versions—No fix listedCNA
  • Cisco Adaptive Security Appliance (ASA) Software VendorCisco Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 4

CPEVersionsRoleVendor
cpe:2.3:a:cisco:adaptive_security_appliance:*:*:*:*:*:*:*:*before 9.6.4.43VulnerableCisco
cpe:2.3:a:cisco:secure_firewall_threat_defense:*:*:*:*:*:*:*:*up to 6.2.2; 6.3.0 to before 6.3.0.6; 6.4.0 to before 6.4.0.10; 6.5.0 to before 6.5.0.5VulnerableCisco
cpe:2.3:a:cisco:secure_firewall_threat_defense:6.6.0:*:*:*:*:*:*:*6.6.0VulnerableCisco
cpe:2.3:o:cisco:adaptive_security_appliance_software:*:*:*:*:*:*:*:*9.7.0 to before 9.8.4.24; 9.9.0 to before 9.9.2.80; 9.10.0 to before 9.10.1.43; 9.12.0 to before 9.12.4.2; 9.13.0 to before 9.13.1.13; 9.14.0 to before 9.14.1.19VulnerableCisco
  • cpe:2.3:a:cisco:adaptive_security_appliance:*:*:*:*:*:*:*:* Versions before 9.6.4.43 Vulnerable ·Cisco
  • cpe:2.3:a:cisco:secure_firewall_threat_defense:*:*:*:*:*:*:*:* Versions up to 6.2.2; 6.3.0 to before 6.3.0.6; 6.4.0 to before 6.4.0.10; 6.5.0 to before 6.5.0.5 Vulnerable ·Cisco
  • cpe:2.3:a:cisco:secure_firewall_threat_defense:6.6.0:*:*:*:*:*:*:* Versions 6.6.0 Vulnerable ·Cisco
  • cpe:2.3:o:cisco:adaptive_security_appliance_software:*:*:*:*:*:*:*:* Versions 9.7.0 to before 9.8.4.24; 9.9.0 to before 9.9.2.80; 9.10.0 to before 9.10.1.43; 9.12.0 to before 9.12.4.2; 9.13.0 to before 9.13.1.13; 9.14.0 to before 9.14.1.19 Vulnerable ·Cisco

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2020-3555
  2. 2026-10-03 Alias added: GHSA-r7x6-g4f2-fq99

References

Advisory 1

  • TI-2020-02861 Uncontrolled resource consumption in Cisco Adaptive Security Appliance Software CVSS 3.1HIGH 8.6
  • TI-2021-17312 Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software SSL/TLS Denial of Service Vulnerability CVSS 3.1HIGH 8.6
  • TI-2020-03115 Uncontrolled resource consumption in Cisco Adaptive Security Appliance Software CVSS 3.1HIGH 8.6
  • TI-2020-03075 Uncontrolled resource consumption in Cisco Adaptive Security Appliance Software CVSS 3.1HIGH 8.6
  • TI-2020-02985 Unrestricted file upload in Cisco Adaptive Security Appliance Software CVSS 3.1HIGH 8.6
  • TI-2021-17313 Stack-based buffer overflow in Cisco Adaptive Security Appliance Software CVSS 3.1HIGH 8.6
See all 62 →

Sources

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