Vulnerability Database

346,508

Total vulnerabilities in the database

CVE-2020-3234 — cisco / ios

Use of Hard-coded Credentials

A vulnerability in the virtual console authentication of Cisco IOS Software for Cisco 809 and 829 Industrial Integrated Services Routers (Industrial ISRs) and Cisco 1000 Series Connected Grid Routers (CGR1000) could allow an authenticated but low-privileged, local attacker to log in to the Virtual Device Server (VDS) of an affected device by using a set of default credentials. The vulnerability is due to the presence of weak, hard-coded credentials. An attacker could exploit this vulnerability by authenticating to the targeted device and then connecting to VDS through the device’s virtual console by using the static credentials. A successful exploit could allow the attacker to access the Linux shell of VDS as the root user.

  • Published: Jun 3, 2020
  • Updated: Nov 16, 2025
  • CVE: CVE-2020-3234
  • Severity: High
  • Exploit:

CVSS v3:

  • Severity: High
  • Score: 8.8
  • AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

CVSS v2:

  • Severity: High
  • Score: 7.2
  • AV:L/AC:L/Au:N/C:C/I:C/A:C

CWEs:

Software From Fixed in
cisco / ios 12.2(60)ez16 12.2(60)ez16.x
cisco / ios 15.0(2)sg11a 15.0(2)sg11a.x
cisco / ios 15.3(3)jaa1 15.3(3)jaa1.x
cisco / ios 15.3(3)jpj 15.3(3)jpj.x
cisco / ios 15.4(1)cg 15.4(1)cg.x
cisco / ios 15.4(2)cg 15.4(2)cg.x
cisco / ios 15.4(3)m 15.4(3)m.x
cisco / ios 15.4(3)m1 15.4(3)m1.x
cisco / ios 15.4(3)m2 15.4(3)m2.x
cisco / ios 15.4(3)m3 15.4(3)m3.x
cisco / ios 15.4(3)m4 15.4(3)m4.x
cisco / ios 15.4(3)m5 15.4(3)m5.x
cisco / ios 15.4(3)m6 15.4(3)m6.x
cisco / ios 15.4(3)m6a 15.4(3)m6a.x
cisco / ios 15.4(3)m7 15.4(3)m7.x
cisco / ios 15.4(3)m8 15.4(3)m8.x
cisco / ios 15.4(3)m9 15.4(3)m9.x
cisco / ios 15.4(3)m10 15.4(3)m10.x
cisco / ios 15.5(1)t 15.5(1)t.x
cisco / ios 15.5(1)t2 15.5(1)t2.x
cisco / ios 15.5(1)t3 15.5(1)t3.x
cisco / ios 15.5(1)t4 15.5(1)t4.x
cisco / ios 15.5(2)t 15.5(2)t.x
cisco / ios 15.5(2)t1 15.5(2)t1.x
cisco / ios 15.5(2)t2 15.5(2)t2.x
cisco / ios 15.5(2)t3 15.5(2)t3.x
cisco / ios 15.5(2)t4 15.5(2)t4.x
cisco / ios 15.5(3)m 15.5(3)m.x
cisco / ios 15.5(3)m0a 15.5(3)m0a.x
cisco / ios 15.5(3)m1 15.5(3)m1.x
cisco / ios 15.5(3)m2 15.5(3)m2.x
cisco / ios 15.5(3)m2a 15.5(3)m2a.x
cisco / ios 15.5(3)m3 15.5(3)m3.x
cisco / ios 15.5(3)m4 15.5(3)m4.x
cisco / ios 15.5(3)m4a 15.5(3)m4a.x
cisco / ios 15.5(3)m5 15.5(3)m5.x
cisco / ios 15.5(3)m6 15.5(3)m6.x
cisco / ios 15.5(3)m6a 15.5(3)m6a.x
cisco / ios 15.5(3)m7 15.5(3)m7.x
cisco / ios 15.5(3)m8 15.5(3)m8.x
cisco / ios 15.5(3)m9 15.5(3)m9.x
cisco / ios 15.5(3)m10 15.5(3)m10.x
cisco / ios 15.5(3)m11 15.5(3)m11.x
cisco / ios 15.6(1)t 15.6(1)t.x
cisco / ios 15.6(1)t0a 15.6(1)t0a.x
cisco / ios 15.6(1)t1 15.6(1)t1.x
cisco / ios 15.6(1)t2 15.6(1)t2.x
cisco / ios 15.6(1)t3 15.6(1)t3.x
cisco / ios 15.6(2)t 15.6(2)t.x
cisco / ios 15.6(2)t1 15.6(2)t1.x
cisco / ios 15.6(2)t2 15.6(2)t2.x
cisco / ios 15.6(2)t3 15.6(2)t3.x
cisco / ios 15.6(3)m 15.6(3)m.x
cisco / ios 15.6(3)m0a 15.6(3)m0a.x
cisco / ios 15.6(3)m1 15.6(3)m1.x
cisco / ios 15.6(3)m1b 15.6(3)m1b.x
cisco / ios 15.6(3)m2 15.6(3)m2.x
cisco / ios 15.6(3)m3 15.6(3)m3.x
cisco / ios 15.6(3)m3a 15.6(3)m3a.x
cisco / ios 15.6(3)m4 15.6(3)m4.x
cisco / ios 15.6(3)m5 15.6(3)m5.x
cisco / ios 15.6(3)m6 15.6(3)m6.x
cisco / ios 15.6(3)m6a 15.6(3)m6a.x
cisco / ios 15.6(3)m6b 15.6(3)m6b.x
cisco / ios 15.6(3)m7 15.6(3)m7.x
cisco / ios 15.6(3)m8 15.6(3)m8.x
cisco / ios 15.6(3)m9 15.6(3)m9.x
cisco / ios 15.7(3)m 15.7(3)m.x
cisco / ios 15.7(3)m1 15.7(3)m1.x
cisco / ios 15.7(3)m2 15.7(3)m2.x
cisco / ios 15.7(3)m3 15.7(3)m3.x
cisco / ios 15.7(3)m4 15.7(3)m4.x
cisco / ios 15.7(3)m4a 15.7(3)m4a.x
cisco / ios 15.7(3)m4b 15.7(3)m4b.x
cisco / ios 15.7(3)m5 15.7(3)m5.x
cisco / ios 15.7(3)m6 15.7(3)m6.x
cisco / ios 15.7(3)m7 15.7(3)m7.x
cisco / ios 15.8(3)m 15.8(3)m.x
cisco / ios 15.8(3)m0a 15.8(3)m0a.x
cisco / ios 15.8(3)m1 15.8(3)m1.x
cisco / ios 15.8(3)m2 15.8(3)m2.x
cisco / ios 15.8(3)m2a 15.8(3)m2a.x
cisco / ios 15.8(3)m3 15.8(3)m3.x
cisco / ios 15.8(3)m3a 15.8(3)m3a.x
cisco / ios 15.8(3)m3b 15.8(3)m3b.x
cisco / ios 15.8(3)m4 15.8(3)m4.x
cisco / ios 15.8(3)m5 15.8(3)m5.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.