Resource exhaustion in Cisco Adaptive Security Appliance Software
CVE-2017-3793
A vulnerability in the TCP normalizer of Cisco Adaptive Security Appliance (ASA) Software (8.0 through 8.7 and 9.0 through 9.6) and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause Cisco ASA and FTD to drop any further incoming traffic on all interfaces, resulting in a denial of service (DoS) condition. The vulnerability is due to improper limitation of the global out-of-order TCP queue for specific block sizes. An attacker could exploit this vulnerability by sending a large number of unique permitted TCP connections with out-of-order segments. An exploit could allow the attacker to exhaust available blocks in the global out-of-order TCP queue, causing the dropping of any further incoming traffic on all interfaces and resulting in a DoS condition. Cisco Bug IDs: CSCvb46321.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 4.0 (Medium). Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:L.
EPSS exploit prediction
EPSS: 0.017 (76.4th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 76th percentile — 76.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.017 · newest: 0.017 · change: 0.000
Affected products
- Cisco Adaptive Security Appliance Software — versions 9.1\(7\)6, 9.1(7)9, 9.1\(7\)7
- Cisco Asa Software And Ftd — versions Cisco ASA Software and Cisco FTD Software
Weakness classification (CWE)
References
- www.securityfocus.com/bid/97923 (VDB Entry, Third Party Advisory, vdb-entry)
- tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170419… (Vendor Advisory)
- www.securitytracker.com/id/1038329 (vdb-entry)
Frequently asked questions
- What is CVE-2017-3793?
- CVE-2017-3793 is a medium-severity vulnerability in Cisco Adaptive Security Appliance Software, classified under CWE-399. CVSS score: 4.0/10. Published 2017-04-20.
- How severe is CVE-2017-3793?
- Medium severity. CVSS v3 base score is 4.0 out of 10.