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TI-2021-17313 Aliases CVE-2021-40118GHSA-6c9f-g24c-wm5r

Stack-based buffer overflow in Cisco Adaptive Security Appliance Software

Priority MEDIUM 46CWE-121Published · 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 · CNA. Fix status from CNA. Impact type from CWE-121 and the CVSS impact.

Summary

A vulnerability in the web services interface of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to trigger a denial of service (DoS) condition. This vulnerability is due to improper input validation when parsing HTTPS requests. An attacker could exploit this vulnerability by sending a malicious HTTPS request to an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.01362 71st 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 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 · 51

CPEVersionsRoleVendor
cpe:2.3:a:cisco:adaptive_security_appliance:*:*:*:*:*:*:*:*before 9.8.4.40VulnerableCisco
cpe:2.3:a:cisco:secure_firewall_threat_defense:*:*:*:*:*:*:*:*before 6.4.0.13; 6.5.0 to before 6.6.5; 6.7.0 to before 6.7.0.3; 7.0.0 to before 7.0.1VulnerableCisco
cpe:2.3:o:cisco:adaptive_security_appliance_software:*:*:*:*:*:*:*:*9.9.0 to before 9.12.4.29; 9.13.0 to before 9.14.3.9; 9.15.0 to before 9.15.1.17; 9.16.0 to before 9.16.2.3VulnerableCisco
cpe:2.3:o:cisco:asa_5512-x_firmware:009.012\(004.024\):*:*:*:*:*:*:*009.012(004.024)VulnerableCisco
cpe:2.3:o:cisco:asa_5512-x_firmware:009.015\(001\):*:*:*:*:*:*:*009.015(001)VulnerableCisco
cpe:2.3:o:cisco:asa_5512-x_firmware:009.015\(001.015\):*:*:*:*:*:*:*009.015(001.015)VulnerableCisco
cpe:2.3:o:cisco:asa_5512-x_firmware:009.015\(001.016\):*:*:*:*:*:*:*009.015(001.016)VulnerableCisco
cpe:2.3:o:cisco:asa_5512-x_firmware:009.016\(001\):*:*:*:*:*:*:*009.016(001)VulnerableCisco
cpe:2.3:h:cisco:asa_5512-x:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:o:cisco:asa_5505_firmware:009.012\(004.024\):*:*:*:*:*:*:*009.012(004.024)VulnerableCisco
  • cpe:2.3:a:cisco:adaptive_security_appliance:*:*:*:*:*:*:*:* Versions before 9.8.4.40 Vulnerable ·Cisco
  • cpe:2.3:a:cisco:secure_firewall_threat_defense:*:*:*:*:*:*:*:* Versions before 6.4.0.13; 6.5.0 to before 6.6.5; 6.7.0 to before 6.7.0.3; 7.0.0 to before 7.0.1 Vulnerable ·Cisco
  • cpe:2.3:o:cisco:adaptive_security_appliance_software:*:*:*:*:*:*:*:* Versions 9.9.0 to before 9.12.4.29; 9.13.0 to before 9.14.3.9; 9.15.0 to before 9.15.1.17; 9.16.0 to before 9.16.2.3 Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5512-x_firmware:009.012\(004.024\):*:*:*:*:*:*:* Versions 009.012(004.024) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5512-x_firmware:009.015\(001\):*:*:*:*:*:*:* Versions 009.015(001) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5512-x_firmware:009.015\(001.015\):*:*:*:*:*:*:* Versions 009.015(001.015) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5512-x_firmware:009.015\(001.016\):*:*:*:*:*:*:* Versions 009.015(001.016) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5512-x_firmware:009.016\(001\):*:*:*:*:*:*:* Versions 009.016(001) Vulnerable ·Cisco
  • cpe:2.3:h:cisco:asa_5512-x:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:o:cisco:asa_5505_firmware:009.012\(004.024\):*:*:*:*:*:*:* Versions 009.012(004.024) Vulnerable ·Cisco
Show 41 more CPE
CPEVersionsRoleVendor
cpe:2.3:o:cisco:asa_5505_firmware:009.015\(001\):*:*:*:*:*:*:*009.015(001)VulnerableCisco
cpe:2.3:o:cisco:asa_5505_firmware:009.015\(001.015\):*:*:*:*:*:*:*009.015(001.015)VulnerableCisco
cpe:2.3:o:cisco:asa_5505_firmware:009.015\(001.016\):*:*:*:*:*:*:*009.015(001.016)VulnerableCisco
cpe:2.3:o:cisco:asa_5505_firmware:009.016\(001\):*:*:*:*:*:*:*009.016(001)VulnerableCisco
cpe:2.3:h:cisco:asa_5505:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:o:cisco:asa_5515-x_firmware:009.012\(004.024\):*:*:*:*:*:*:*009.012(004.024)VulnerableCisco
cpe:2.3:o:cisco:asa_5515-x_firmware:009.015\(001\):*:*:*:*:*:*:*009.015(001)VulnerableCisco
cpe:2.3:o:cisco:asa_5515-x_firmware:009.015\(001.015\):*:*:*:*:*:*:*009.015(001.015)VulnerableCisco
cpe:2.3:o:cisco:asa_5515-x_firmware:009.015\(001.016\):*:*:*:*:*:*:*009.015(001.016)VulnerableCisco
cpe:2.3:o:cisco:asa_5515-x_firmware:009.016\(001\):*:*:*:*:*:*:*009.016(001)VulnerableCisco
cpe:2.3:h:cisco:asa_5515-x:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:o:cisco:asa_5525-x_firmware:009.012\(004.024\):*:*:*:*:*:*:*009.012(004.024)VulnerableCisco
cpe:2.3:o:cisco:asa_5525-x_firmware:009.015\(001\):*:*:*:*:*:*:*009.015(001)VulnerableCisco
cpe:2.3:o:cisco:asa_5525-x_firmware:009.015\(001.015\):*:*:*:*:*:*:*009.015(001.015)VulnerableCisco
cpe:2.3:o:cisco:asa_5525-x_firmware:009.015\(001.016\):*:*:*:*:*:*:*009.015(001.016)VulnerableCisco
cpe:2.3:o:cisco:asa_5525-x_firmware:009.016\(001\):*:*:*:*:*:*:*009.016(001)VulnerableCisco
cpe:2.3:h:cisco:asa_5525-x:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:o:cisco:asa_5545-x_firmware:009.012\(004.024\):*:*:*:*:*:*:*009.012(004.024)VulnerableCisco
cpe:2.3:o:cisco:asa_5545-x_firmware:009.015\(001\):*:*:*:*:*:*:*009.015(001)VulnerableCisco
cpe:2.3:o:cisco:asa_5545-x_firmware:009.015\(001.015\):*:*:*:*:*:*:*009.015(001.015)VulnerableCisco
cpe:2.3:o:cisco:asa_5545-x_firmware:009.015\(001.016\):*:*:*:*:*:*:*009.015(001.016)VulnerableCisco
cpe:2.3:o:cisco:asa_5545-x_firmware:009.016\(001\):*:*:*:*:*:*:*009.016(001)VulnerableCisco
cpe:2.3:h:cisco:asa_5545-x:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:o:cisco:asa_5555-x_firmware:009.012\(004.024\):*:*:*:*:*:*:*009.012(004.024)VulnerableCisco
cpe:2.3:o:cisco:asa_5555-x_firmware:009.015\(001\):*:*:*:*:*:*:*009.015(001)VulnerableCisco
cpe:2.3:o:cisco:asa_5555-x_firmware:009.015\(001.015\):*:*:*:*:*:*:*009.015(001.015)VulnerableCisco
cpe:2.3:o:cisco:asa_5555-x_firmware:009.015\(001.016\):*:*:*:*:*:*:*009.015(001.016)VulnerableCisco
cpe:2.3:o:cisco:asa_5555-x_firmware:009.016\(001\):*:*:*:*:*:*:*009.016(001)VulnerableCisco
cpe:2.3:h:cisco:asa_5555-x:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:o:cisco:asa_5580_firmware:009.012\(004.024\):*:*:*:*:*:*:*009.012(004.024)VulnerableCisco
cpe:2.3:o:cisco:asa_5580_firmware:009.015\(001\):*:*:*:*:*:*:*009.015(001)VulnerableCisco
cpe:2.3:o:cisco:asa_5580_firmware:009.015\(001.015\):*:*:*:*:*:*:*009.015(001.015)VulnerableCisco
cpe:2.3:o:cisco:asa_5580_firmware:009.015\(001.016\):*:*:*:*:*:*:*009.015(001.016)VulnerableCisco
cpe:2.3:o:cisco:asa_5580_firmware:009.016\(001\):*:*:*:*:*:*:*009.016(001)VulnerableCisco
cpe:2.3:h:cisco:asa_5580:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:o:cisco:asa_5585-x_firmware:009.012\(004.024\):*:*:*:*:*:*:*009.012(004.024)VulnerableCisco
cpe:2.3:o:cisco:asa_5585-x_firmware:009.015\(001\):*:*:*:*:*:*:*009.015(001)VulnerableCisco
cpe:2.3:o:cisco:asa_5585-x_firmware:009.015\(001.015\):*:*:*:*:*:*:*009.015(001.015)VulnerableCisco
cpe:2.3:o:cisco:asa_5585-x_firmware:009.015\(001.016\):*:*:*:*:*:*:*009.015(001.016)VulnerableCisco
cpe:2.3:o:cisco:asa_5585-x_firmware:009.016\(001\):*:*:*:*:*:*:*009.016(001)VulnerableCisco
cpe:2.3:h:cisco:asa_5585-x:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
  • cpe:2.3:o:cisco:asa_5505_firmware:009.015\(001\):*:*:*:*:*:*:* Versions 009.015(001) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5505_firmware:009.015\(001.015\):*:*:*:*:*:*:* Versions 009.015(001.015) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5505_firmware:009.015\(001.016\):*:*:*:*:*:*:* Versions 009.015(001.016) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5505_firmware:009.016\(001\):*:*:*:*:*:*:* Versions 009.016(001) Vulnerable ·Cisco
  • cpe:2.3:h:cisco:asa_5505:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:o:cisco:asa_5515-x_firmware:009.012\(004.024\):*:*:*:*:*:*:* Versions 009.012(004.024) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5515-x_firmware:009.015\(001\):*:*:*:*:*:*:* Versions 009.015(001) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5515-x_firmware:009.015\(001.015\):*:*:*:*:*:*:* Versions 009.015(001.015) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5515-x_firmware:009.015\(001.016\):*:*:*:*:*:*:* Versions 009.015(001.016) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5515-x_firmware:009.016\(001\):*:*:*:*:*:*:* Versions 009.016(001) Vulnerable ·Cisco
  • cpe:2.3:h:cisco:asa_5515-x:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:o:cisco:asa_5525-x_firmware:009.012\(004.024\):*:*:*:*:*:*:* Versions 009.012(004.024) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5525-x_firmware:009.015\(001\):*:*:*:*:*:*:* Versions 009.015(001) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5525-x_firmware:009.015\(001.015\):*:*:*:*:*:*:* Versions 009.015(001.015) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5525-x_firmware:009.015\(001.016\):*:*:*:*:*:*:* Versions 009.015(001.016) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5525-x_firmware:009.016\(001\):*:*:*:*:*:*:* Versions 009.016(001) Vulnerable ·Cisco
  • cpe:2.3:h:cisco:asa_5525-x:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:o:cisco:asa_5545-x_firmware:009.012\(004.024\):*:*:*:*:*:*:* Versions 009.012(004.024) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5545-x_firmware:009.015\(001\):*:*:*:*:*:*:* Versions 009.015(001) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5545-x_firmware:009.015\(001.015\):*:*:*:*:*:*:* Versions 009.015(001.015) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5545-x_firmware:009.015\(001.016\):*:*:*:*:*:*:* Versions 009.015(001.016) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5545-x_firmware:009.016\(001\):*:*:*:*:*:*:* Versions 009.016(001) Vulnerable ·Cisco
  • cpe:2.3:h:cisco:asa_5545-x:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:o:cisco:asa_5555-x_firmware:009.012\(004.024\):*:*:*:*:*:*:* Versions 009.012(004.024) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5555-x_firmware:009.015\(001\):*:*:*:*:*:*:* Versions 009.015(001) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5555-x_firmware:009.015\(001.015\):*:*:*:*:*:*:* Versions 009.015(001.015) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5555-x_firmware:009.015\(001.016\):*:*:*:*:*:*:* Versions 009.015(001.016) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5555-x_firmware:009.016\(001\):*:*:*:*:*:*:* Versions 009.016(001) Vulnerable ·Cisco
  • cpe:2.3:h:cisco:asa_5555-x:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:o:cisco:asa_5580_firmware:009.012\(004.024\):*:*:*:*:*:*:* Versions 009.012(004.024) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5580_firmware:009.015\(001\):*:*:*:*:*:*:* Versions 009.015(001) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5580_firmware:009.015\(001.015\):*:*:*:*:*:*:* Versions 009.015(001.015) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5580_firmware:009.015\(001.016\):*:*:*:*:*:*:* Versions 009.015(001.016) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5580_firmware:009.016\(001\):*:*:*:*:*:*:* Versions 009.016(001) Vulnerable ·Cisco
  • cpe:2.3:h:cisco:asa_5580:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:o:cisco:asa_5585-x_firmware:009.012\(004.024\):*:*:*:*:*:*:* Versions 009.012(004.024) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5585-x_firmware:009.015\(001\):*:*:*:*:*:*:* Versions 009.015(001) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5585-x_firmware:009.015\(001.015\):*:*:*:*:*:*:* Versions 009.015(001.015) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5585-x_firmware:009.015\(001.016\):*:*:*:*:*:*:* Versions 009.015(001.016) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5585-x_firmware:009.016\(001\):*:*:*:*:*:*:* Versions 009.016(001) Vulnerable ·Cisco
  • cpe:2.3:h:cisco:asa_5585-x:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-40118
  2. 2026-10-03 Alias added: GHSA-6c9f-g24c-wm5r

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-2021-01297 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