Vulnerability Database

393,544

Total vulnerabilities in the database

CVE-2020-3235 — cisco / ios

Improper Input Validation

A vulnerability in the Simple Network Management Protocol (SNMP) subsystem of Cisco IOS Software and Cisco IOS XE Software on Catalyst 4500 Series Switches could allow an authenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to insufficient input validation when the software processes specific SNMP object identifiers. An attacker could exploit this vulnerability by sending a crafted SNMP packet to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition. Note: To exploit this vulnerability by using SNMPv2c or earlier, the attacker must know the SNMP read-only community string for an affected system. To exploit this vulnerability by using SNMPv3, the attacker must know the user credentials for the affected system.

  • Published: Jun 3, 2020
  • Updated: Oct 4, 2026
  • CVE: CVE-2020-3235
  • Severity: High
  • Exploit:
  • CISA KEV:

CVSS v3:

  • Severity: High
  • Score: 7.7
  • AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H

CVSS v2:

  • Severity: Medium
  • Score: 6.3
  • AV:N/AC:M/Au:S/C:N/I:N/A:C
Software Affected versions
cisco / ios = 12.2(52)sg
cisco / ios = 12.2(53)sg1
cisco / ios = 12.2(53)sg2
cisco / ios = 12.2(53)sg3
cisco / ios = 12.2(53)sg4
cisco / ios = 12.2(53)sg5
cisco / ios = 12.2(53)sg6
cisco / ios = 12.2(53)sg7
cisco / ios = 12.2(53)sg8
cisco / ios = 12.2(53)sg9
cisco / ios = 12.2(53)sg10
cisco / ios = 12.2(53)sg11
cisco / ios = 12.2(54)sg
cisco / ios = 12.2(54)sg1
cisco / ios = 12.2(54)wo
cisco / ios = 15.0(1)ey
cisco / ios = 15.0(1)ey2
cisco / ios = 15.0(1)xo
cisco / ios = 15.0(1)xo1
cisco / ios = 15.0(2)ex2
cisco / ios = 15.0(2)ex8
cisco / ios = 15.0(2)sg
cisco / ios = 15.0(2)sg1
cisco / ios = 15.0(2)sg2
cisco / ios = 15.0(2)sg3
cisco / ios = 15.0(2)sg4
cisco / ios = 15.0(2)sg5
cisco / ios = 15.0(2)sg6
cisco / ios = 15.0(2)sg7
cisco / ios = 15.0(2)sg8
cisco / ios = 15.0(2)sg9
cisco / ios = 15.0(2)sg10
cisco / ios = 15.0(2)sg11
cisco / ios = 15.0(2)xo
cisco / ios = 15.1(1)sg
cisco / ios = 15.1(1)sg1
cisco / ios = 15.1(1)sg2
cisco / ios = 15.1(2)sg
cisco / ios = 15.1(2)sg1
cisco / ios = 15.1(2)sg2
cisco / ios = 15.1(2)sg3
cisco / ios = 15.1(2)sg4
cisco / ios = 15.1(2)sg5
cisco / ios = 15.1(2)sg6
cisco / ios = 15.1(2)sg7
cisco / ios = 15.1(2)sg8
cisco / ios = 15.2(1)e
cisco / ios = 15.2(1)e1
cisco / ios = 15.2(1)e3
cisco / ios = 15.2(2)e
cisco / ios = 15.2(2)e1
cisco / ios = 15.2(2)e2
cisco / ios = 15.2(2)e3
cisco / ios = 15.2(2)e4
cisco / ios = 15.2(2)e5
cisco / ios = 15.2(2)e5a
cisco / ios = 15.2(2)e5b
cisco / ios = 15.2(2)e6
cisco / ios = 15.2(2)e7
cisco / ios = 15.2(2)e7b
cisco / ios = 15.2(2)e8
cisco / ios = 15.2(2)e9
cisco / ios = 15.2(2)e9a
cisco / ios = 15.2(2)e10
cisco / ios = 15.2(2b)e
cisco / ios = 15.2(3)e
cisco / ios = 15.2(3)e1
cisco / ios = 15.2(3)e2
cisco / ios = 15.2(3)e3
cisco / ios = 15.2(3)e4
cisco / ios = 15.2(3)e5
cisco / ios = 15.2(4)e
cisco / ios = 15.2(4)e1
cisco / ios = 15.2(4)e2
cisco / ios = 15.2(4)e3
cisco / ios = 15.2(4)e4
cisco / ios = 15.2(4)e5
cisco / ios = 15.2(4)e5a
cisco / ios = 15.2(4)e6
cisco / ios = 15.2(4)e7
cisco / ios = 15.2(4)e8
cisco / ios = 15.3(3)jpj
cisco / ios_xe = 3.2.0sg
cisco / ios_xe = 3.2.1sg
cisco / ios_xe = 3.2.2sg
cisco / ios_xe = 3.2.3sg
cisco / ios_xe = 3.2.4sg
cisco / ios_xe = 3.2.5sg
cisco / ios_xe = 3.2.6sg
cisco / ios_xe = 3.2.7sg
cisco / ios_xe = 3.2.8sg
cisco / ios_xe = 3.2.9sg
cisco / ios_xe = 3.2.10sg
cisco / ios_xe = 3.2.11sg
cisco / ios_xe = 3.3.0sg
cisco / ios_xe = 3.3.0xo
cisco / ios_xe = 3.3.1sg
cisco / ios_xe = 3.3.1xo
cisco / ios_xe = 3.3.2sg
cisco / ios_xe = 3.3.2xo
cisco / ios_xe = 3.4.0sg
cisco / ios_xe = 3.4.1sg
cisco / ios_xe = 3.4.2sg
cisco / ios_xe = 3.4.3sg
cisco / ios_xe = 3.4.4sg
cisco / ios_xe = 3.4.5sg
cisco / ios_xe = 3.4.6sg
cisco / ios_xe = 3.4.7sg
cisco / ios_xe = 3.4.8sg
cisco / ios_xe = 3.5.0e
cisco / ios_xe = 3.5.1e
cisco / ios_xe = 3.5.2e
cisco / ios_xe = 3.5.3e
cisco / ios_xe = 3.6.0be
cisco / ios_xe = 3.6.0e
cisco / ios_xe = 3.6.1e
cisco / ios_xe = 3.6.3e
cisco / ios_xe = 3.6.4e
cisco / ios_xe = 3.6.5ae
cisco / ios_xe = 3.6.5be
cisco / ios_xe = 3.6.5e
cisco / ios_xe = 3.6.6e
cisco / ios_xe = 3.6.7e
cisco / ios_xe = 3.6.8e
cisco / ios_xe = 3.6.9e
cisco / ios_xe = 3.6.10e
cisco / ios_xe = 3.7.0e
cisco / ios_xe = 3.7.1e
cisco / ios_xe = 3.7.2e
cisco / ios_xe = 3.7.3e
cisco / ios_xe = 3.8.0e
cisco / ios_xe = 3.8.1e
cisco / ios_xe = 3.8.2e
cisco / ios_xe = 3.8.3e
cisco / ios_xe = 3.8.4e
cisco / ios_xe = 3.8.5ae
cisco / ios_xe = 3.8.5e
cisco / ios_xe = 3.8.6e
cisco / ios_xe = 3.8.7e
cisco / ios_xe = 3.8.8e
cisco / ios_xe = 3.9.0e
cisco / ios_xe = 3.9.1e
cisco / ios_xe = 3.9.2be
cisco / ios_xe = 3.9.2e
cisco / ios_xe = 3.10.0ce
cisco / ios_xe = 3.10.0e
cisco / ios_xe = 3.10.1ae
cisco / ios_xe = 3.10.1e
cisco / ios_xe = 3.10.1se
cisco / ios_xe = 3.10.2e
oracle / goldengate_management_pack = 12.2.1.2.0

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.