Vulnerability Database

327,594

Total vulnerabilities in the database

CVE-2016-7551

chain_sip in Asterisk Open Source 11.x before 11.23.1 and 13.x 13.11.1 and Certified Asterisk 11.6 before 11.6-cert15 and 13.8 before 13.8-cert3 allows remote attackers to cause a denial of service (port exhaustion).

  • Published: Apr 17, 2017
  • Updated: Nov 9, 2025
  • CVE: CVE-2016-7551
  • Severity: Medium
  • Exploit:

CVSS v2:

  • Severity: Medium
  • Score: 5
  • AV:N/AC:L/Au:N/C:N/I:N/A:P

CWEs:

Software From Fixed in
digium / asterisk 13.1.0 13.1.0.x
digium / asterisk 13.2.1 13.2.1.x
digium / asterisk 13.8.0-rc1 13.8.0-rc1.x
digium / asterisk 11.14.0 11.14.0.x
digium / asterisk 13.7.1 13.7.1.x
digium / asterisk 11.2.0-rc2 11.2.0-rc2.x
digium / asterisk 11.21.0 11.21.0.x
digium / asterisk 11.22.0 11.22.0.x
digium / asterisk 11.10.2 11.10.2.x
digium / asterisk 11.0.0-rc2 11.0.0-rc2.x
digium / asterisk 11.2.0 11.2.0.x
digium / asterisk 11.1.1 11.1.1.x
digium / asterisk 13.1.1 13.1.1.x
digium / asterisk 11.21.1 11.21.1.x
digium / asterisk 13.4.0 13.4.0.x
digium / asterisk 11.10.1 11.10.1.x
digium / asterisk 11.16.0 11.16.0.x
digium / asterisk 11.11.0 11.11.0.x
digium / asterisk 11.12.1 11.12.1.x
digium / asterisk 11.23.0-rc1 11.23.0-rc1.x
digium / asterisk 13.2.0 13.2.0.x
digium / asterisk 11.0.2 11.0.2.x
digium / asterisk 11.2.0-rc1 11.2.0-rc1.x
digium / asterisk 11.0.0-beta1 11.0.0-beta1.x
digium / asterisk 11.18.0 11.18.0.x
digium / asterisk 11.17.0 11.17.0.x
digium / asterisk 13.3.2 13.3.2.x
digium / asterisk 13.0.1 13.0.1.x
digium / asterisk 11.7.0 11.7.0.x
digium / asterisk 11.22.0-rc1 11.22.0-rc1.x
digium / asterisk 13.7.0 13.7.0.x
digium / asterisk 11.12.0 11.12.0.x
digium / asterisk 13.10.0-rc1 13.10.0-rc1.x
digium / asterisk 13.10.0 13.10.0.x
digium / asterisk 11.15.1 11.15.1.x
digium / asterisk 11.0.0 11.0.0.x
digium / asterisk 11.10.0 11.10.0.x
digium / asterisk 13.8.0 13.8.0.x
digium / asterisk 11.4.0 11.4.0.x
digium / asterisk 13.11.0 13.11.0.x
digium / asterisk 11.13.0 11.13.0.x
digium / asterisk 13.9.0 13.9.0.x
digium / asterisk 13.3.0 13.3.0.x
digium / asterisk 13.8.1 13.8.1.x
digium / asterisk 11.1.0-rc3 11.1.0-rc3.x
digium / asterisk 13.0.0-beta1 13.0.0-beta1.x
digium / asterisk 11.8.1 11.8.1.x
digium / asterisk 11.19.0 11.19.0.x
digium / asterisk 11.1.2 11.1.2.x
digium / asterisk 13.0.0 13.0.0.x
digium / asterisk 11.21.2 11.21.2.x
digium / asterisk 11.14.2 11.14.2.x
digium / asterisk 13.9.1 13.9.1.x
digium / asterisk 11.5.0 11.5.0.x
digium / asterisk 11.15.0 11.15.0.x
digium / asterisk 13.3.1 13.3.1.x
digium / asterisk 11.2.2 11.2.2.x
digium / asterisk 11.14.1 11.14.1.x
digium / asterisk 13.0.2 13.0.2.x
digium / asterisk 11.1.0 11.1.0.x
digium / asterisk 13.7.2 13.7.2.x
digium / asterisk 11.17.1 11.17.1.x
digium / asterisk 11.0.0-beta2 11.0.0-beta2.x
digium / asterisk 11.1.0-rc1 11.1.0-rc1.x
digium / asterisk 11.0.1 11.0.1.x
digium / asterisk 11.8.0 11.8.0.x
digium / asterisk 11.6.0 11.6.0.x
digium / asterisk 13.5.0 13.5.0.x
digium / asterisk 11.23.0 11.23.0.x
digium / asterisk 13.8.2 13.8.2.x
digium / asterisk 13.0.0-beta3 13.0.0-beta3.x
digium / asterisk 13.6.0 13.6.0.x
digium / asterisk 11.9.0 11.9.0.x
digium / asterisk 11.2.1 11.2.1.x
digium / asterisk 11.5.1 11.5.1.x
digium / asterisk 11.3.0 11.3.0.x
digium / asterisk 11.13.1 11.13.1.x
digium / asterisk 11.20.0 11.20.0.x
digium / asterisk 13.0.0-beta2 13.0.0-beta2.x
digium / asterisk 11.6.1 11.6.1.x
digium / asterisk 11.0.0-rc1 11.0.0-rc1.x
digium / certified_asterisk 11.6-cert13 11.6-cert13.x
digium / certified_asterisk 11.6-cert8 11.6-cert8.x
digium / certified_asterisk 11.6-cert2 11.6-cert2.x
digium / certified_asterisk 11.6-cert7 11.6-cert7.x
digium / certified_asterisk 13.8-cert1 13.8-cert1.x
digium / certified_asterisk 11.6-cert4 11.6-cert4.x
digium / certified_asterisk 11.6-cert3 11.6-cert3.x
digium / certified_asterisk 11.6-cert9 11.6-cert9.x
digium / certified_asterisk 13.8-cert1_rc2 13.8-cert1_rc2.x
digium / certified_asterisk 11.6-cert12 11.6-cert12.x
digium / certified_asterisk 11.6-cert1 11.6-cert1.x
digium / certified_asterisk 11.6.0 11.6.0.x
digium / certified_asterisk 11.6-cert1_rc2 11.6-cert1_rc2.x
digium / certified_asterisk 13.8-cert1_rc3 13.8-cert1_rc3.x
digium / certified_asterisk 13.8.0 13.8.0.x
digium / certified_asterisk 11.6-cert14 11.6-cert14.x
digium / certified_asterisk 11.6-cert15 11.6-cert15.x
digium / certified_asterisk 11.6.0-rc1 11.6.0-rc1.x
digium / certified_asterisk 13.8.0-rc1 13.8.0-rc1.x
digium / certified_asterisk 11.6-cert1_rc1 11.6-cert1_rc1.x
digium / certified_asterisk 11.6-cert11 11.6-cert11.x
digium / certified_asterisk 13.8-cert1_rc1 13.8-cert1_rc1.x
digium / certified_asterisk 11.6-cert6 11.6-cert6.x
digium / certified_asterisk 11.6-cert10 11.6-cert10.x
digium / certified_asterisk 13.8-cert2_rc1 13.8-cert2_rc1.x
digium / certified_asterisk 11.6-cert5 11.6-cert5.x
digium / certified_asterisk 11.6.0-rc2 11.6.0-rc2.x
debian / debian_linux 8.0 8.0.x

Frequently Asked Questions

A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.

A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. In practice, risk increases sharply when exploitation becomes reliable or widespread.

Recurring findings usually come from incomplete Asset Discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host. Unknown or unmanaged assets (often called Shadow IT) are a common reason the same issues resurface.

Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.

SynScan combines attack surface monitoring and continuous security auditing to keep your inventory current, flag high-impact vulnerabilities early, and help you turn raw findings into a practical remediation plan.