Buffer overflow in Cisco Adaptive Security Appliance Software
CVE-2021-34783
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.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.6 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.016 (74.8th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 75th percentile — 74.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.016 · newest: 0.016 · change: 0.000
Affected products
- Cisco Adaptive Security Appliance Software
- Cisco Asa 5505
- Cisco Asa 5505 Firmware — versions 009.016\(001\), 009.016(001), 009.016(001.025)
- Cisco Asa 5512-X
- Cisco Asa 5512-X Firmware — versions 009.016\(001\), 009.016(001), 009.016(001.025)
- Cisco Asa 5515-X
- Cisco Asa 5515-X Firmware — versions 009.016\(001\), 009.016(001), 009.016(001.025)
- Cisco Asa 5525-X
- Cisco Asa 5525-X Firmware — versions 009.016\(001\), 009.016(001), 009.016(001.025)
- Cisco Asa 5545-X
Weakness classification (CWE)
References
- tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-tls-… (vendor-advisory, Vendor Advisory)
Frequently asked questions
- What is CVE-2021-34783?
- CVE-2021-34783 is a high-severity vulnerability in Cisco Adaptive Security Appliance Software, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 8.6/10. Published 2021-10-27.
- How severe is CVE-2021-34783?
- High severity. CVSS v3 base score is 8.6 out of 10.