CVE-2019-1687 json
Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software TCP Proxy Denial of Service Vulnerability
published 2019-05-03 7 y ago modified 2026-08-11 2 mo ago also EUVD-2019-10244
- cvss
- 6.8
- version 3.0, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 2.9%
- EPSS 2.9% chance of exploitation in 30 days, percentile 87%
- public exploits
- 0
- none known
Summary
A vulnerability in the TCP proxy functionality for Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the device to restart unexpectedly, resulting in a denial of service (DoS) condition. The vulnerability is due to an error in TCP-based packet inspection, which could cause the TCP packet to have an invalid Layer 2 (L2)-formatted header. An attacker could exploit this vulnerability by sending a crafted TCP packet sequence to the targeted device. A successful exploit could allow the attacker to cause a DoS condition.
Patch / fix
- Cisco Cisco Adaptive Security Appliance (ASA) Software 9.4.4.34, 9.8.4, 9.9.2.50
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 23 mo ago
Exploit prediction
2.93% chance of exploitation in the next 30 days, higher than 87% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.0 | 6.8 | CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:H |
| NVD | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVD | 2.0 | 7.8 | AV:N/AC:L/Au:N/C:N/I:N/A:C |
Affected products
- Cisco Cisco Adaptive Security Appliance (ASA) Software
Classification
- Weakness
-
- CWE-20 Improper Input Validation
References
-
tools.cisco.com
/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190501-asa-ftdtcp-dos
vendor-advisory
-
securityfocus.com
/bid/108176
vdb-entry, broken-link, third-party-advisory
Sources
- CVE List CVE-2019-1687
- NVD CVE-2019-1687
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.