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TI-2021-13781 Aliases CVE-2021-34783GHSA-vwpf-cvqf-r3h9

Memory corruption in Cisco Adaptive Security Appliance Software

Priority MEDIUM 46CWE-119Published · 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-119 and the CVSS impact.

Summary

A vulnerability in the software-based SSL/TLS message handler of Cisco Adaptive Security Appliance (ASA) Software and Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition. This vulnerability is due to insufficient validation of SSL/TLS messages when the device performs software-based SSL/TLS decryption. An attacker could exploit this vulnerability by sending a crafted SSL/TLS message to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition. Note: Datagram TLS (DTLS) messages cannot be used to exploit this vulnerability.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.01614 76th 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 · 26

CPEVersionsRoleVendor
cpe:2.3:a:cisco:secure_firewall_threat_defense:*:*:*:*:*:*:*:*6.4.0 to before 6.4.0.13; 6.6.0 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:*:*:*:*:*:*:*:*9.8.0 to before 9.8.4.40; 9.12.0 to before 9.12.4.29; 9.14.0 to before 9.14.3.9; 9.15.0 to before 9.15.1.17; 9.16.0 to before 9.16.2VulnerableCisco
cpe:2.3:o:cisco:asa_5512-x_firmware:009.016\(001\):*:*:*:*:*:*:*009.016(001)VulnerableCisco
cpe:2.3:o:cisco:asa_5512-x_firmware:009.016\(001.025\):*:*:*:*:*:*:*009.016(001.025)VulnerableCisco
cpe:2.3:h:cisco:asa_5512-x:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:o:cisco:asa_5505_firmware:009.016\(001\):*:*:*:*:*:*:*009.016(001)VulnerableCisco
cpe:2.3:o:cisco:asa_5505_firmware:009.016\(001.025\):*:*:*:*:*:*:*009.016(001.025)VulnerableCisco
cpe:2.3:h:cisco:asa_5505:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:o:cisco:asa_5515-x_firmware:009.016\(001\):*:*:*:*:*:*:*009.016(001)VulnerableCisco
cpe:2.3:o:cisco:asa_5515-x_firmware:009.016\(001.025\):*:*:*:*:*:*:*009.016(001.025)VulnerableCisco
  • cpe:2.3:a:cisco:secure_firewall_threat_defense:*:*:*:*:*:*:*:* Versions 6.4.0 to before 6.4.0.13; 6.6.0 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 9.8.0 to before 9.8.4.40; 9.12.0 to before 9.12.4.29; 9.14.0 to before 9.14.3.9; 9.15.0 to before 9.15.1.17; 9.16.0 to before 9.16.2 Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5512-x_firmware:009.016\(001\):*:*:*:*:*:*:* Versions 009.016(001) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5512-x_firmware:009.016\(001.025\):*:*:*:*:*:*:* Versions 009.016(001.025) 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:009.016\(001\):*:*:*:*:*:*:* Versions 009.016(001) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5505_firmware:009.016\(001.025\):*:*:*:*:*:*:* Versions 009.016(001.025) 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:009.016\(001\):*:*:*:*:*:*:* Versions 009.016(001) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5515-x_firmware:009.016\(001.025\):*:*:*:*:*:*:* Versions 009.016(001.025) Vulnerable ·Cisco
Show 16 more CPE
CPEVersionsRoleVendor
cpe:2.3:h:cisco:asa_5515-x:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:o:cisco:asa_5525-x_firmware:009.016\(001\):*:*:*:*:*:*:*009.016(001)VulnerableCisco
cpe:2.3:o:cisco:asa_5525-x_firmware:009.016\(001.025\):*:*:*:*:*:*:*009.016(001.025)VulnerableCisco
cpe:2.3:h:cisco:asa_5525-x:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:o:cisco:asa_5545-x_firmware:009.016\(001\):*:*:*:*:*:*:*009.016(001)VulnerableCisco
cpe:2.3:o:cisco:asa_5545-x_firmware:009.016\(001.025\):*:*:*:*:*:*:*009.016(001.025)VulnerableCisco
cpe:2.3:h:cisco:asa_5545-x:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:o:cisco:asa_5555-x_firmware:009.016\(001\):*:*:*:*:*:*:*009.016(001)VulnerableCisco
cpe:2.3:o:cisco:asa_5555-x_firmware:009.016\(001.025\):*:*:*:*:*:*:*009.016(001.025)VulnerableCisco
cpe:2.3:h:cisco:asa_5555-x:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:o:cisco:asa_5580_firmware:009.016\(001\):*:*:*:*:*:*:*009.016(001)VulnerableCisco
cpe:2.3:o:cisco:asa_5580_firmware:009.016\(001.025\):*:*:*:*:*:*:*009.016(001.025)VulnerableCisco
cpe:2.3:h:cisco:asa_5580:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:o:cisco:asa_5585-x_firmware:009.016\(001\):*:*:*:*:*:*:*009.016(001)VulnerableCisco
cpe:2.3:o:cisco:asa_5585-x_firmware:009.016\(001.025\):*:*:*:*:*:*:*009.016(001.025)VulnerableCisco
cpe:2.3:h:cisco:asa_5585-x:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
  • 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:009.016\(001\):*:*:*:*:*:*:* Versions 009.016(001) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5525-x_firmware:009.016\(001.025\):*:*:*:*:*:*:* Versions 009.016(001.025) 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:009.016\(001\):*:*:*:*:*:*:* Versions 009.016(001) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5545-x_firmware:009.016\(001.025\):*:*:*:*:*:*:* Versions 009.016(001.025) 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:009.016\(001\):*:*:*:*:*:*:* Versions 009.016(001) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5555-x_firmware:009.016\(001.025\):*:*:*:*:*:*:* Versions 009.016(001.025) 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:009.016\(001\):*:*:*:*:*:*:* Versions 009.016(001) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5580_firmware:009.016\(001.025\):*:*:*:*:*:*:* Versions 009.016(001.025) 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:009.016\(001\):*:*:*:*:*:*:* Versions 009.016(001) Vulnerable ·Cisco
  • cpe:2.3:o:cisco:asa_5585-x_firmware:009.016\(001.025\):*:*:*:*:*:*:* Versions 009.016(001.025) 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-2021-34783
  2. 2026-10-03 Alias added: GHSA-vwpf-cvqf-r3h9

References

Advisory 1

  • TI-2025-14628 Buffer overflow in Cisco Secure Firewall Adaptive Security Appliance Software KEVCVSS 3.1CRITICAL 9.9
  • TI-2016-05454 Buffer overflow in Cisco Adaptive Security Appliance (ASA) Software through 9.4.2.3 on… KEVCVSS 3.1HIGH 8.8
  • TI-2023-06973 Authentication bypass in Cisco Adaptive Security Appliance Software KEVCVSS 3.1CRITICAL 9.1
  • TI-2026-82192 Denial of service in Cisco Secure Firewall ASA and FTD SSL VPN KEVCVSS 3.1HIGH 8.6
  • TI-2026-16533 Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense… KEVCVSS 3.1HIGH 8.6
  • TI-2025-14657 Missing authorization in Cisco Secure Firewall Adaptive Security Appliance Software KEVCVSS 3.1HIGH 8.6
See all 354 →

Sources

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