CVE-2021-34783
Last modified
CVE-2021-34783 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. 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. EPSS estimates a 1.55% chance of exploitation in the next 30 days.
Description
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.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Cisco | Firepower Threat Defense | >= 6.4.0, < 6.4.0.13 |
| Cisco | Firepower Threat Defense | >= 6.6.0, < 6.6.5 |
| Cisco | Firepower Threat Defense | >= 6.7.0, < 6.7.0.3 |
| Cisco | Firepower Threat Defense | >= 7.0.0, < 7.0.1 |
| Cisco | Adaptive Security Appliance Software | >= 9.8.0, < 9.8.4.40 |
| Cisco | Adaptive Security Appliance Software | >= 9.12.0, < 9.12.4.29 |
| Cisco | Adaptive Security Appliance Software | >= 9.14.0, < 9.14.3.9 |
| Cisco | Adaptive Security Appliance Software | >= 9.15.0, < 9.15.1.17 |
| Cisco | Adaptive Security Appliance Software | >= 9.16.0, < 9.16.2 |
| Cisco | Asa 5512-X Firmware | 009.016\(001\) |
| Cisco | Asa 5512-X Firmware | 009.016\(001.025\) |
| Cisco | Asa 5505 Firmware | 009.016\(001\) |
| Cisco | Asa 5505 Firmware | 009.016\(001.025\) |
| Cisco | Asa 5515-X Firmware | 009.016\(001\) |
| Cisco | Asa 5515-X Firmware | 009.016\(001.025\) |
| Cisco | Asa 5525-X Firmware | 009.016\(001\) |
| Cisco | Asa 5525-X Firmware | 009.016\(001.025\) |
| Cisco | Asa 5545-X Firmware | 009.016\(001\) |
| Cisco | Asa 5545-X Firmware | 009.016\(001.025\) |
| Cisco | Asa 5555-X Firmware | 009.016\(001\) |
| Cisco | Asa 5555-X Firmware | 009.016\(001.025\) |
| Cisco | Asa 5580 Firmware | 009.016\(001\) |
| Cisco | Asa 5580 Firmware | 009.016\(001.025\) |
| Cisco | Asa 5585-X Firmware | 009.016\(001\) |
| Cisco | Asa 5585-X Firmware | 009.016\(001.025\) |
References
Timeline
- Published
- Last Modified
- Status
- Modified
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How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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