Vulnerability Database

328,409

Total vulnerabilities in the database

CVE-2021-1385

A vulnerability in the Cisco IOx application hosting environment of multiple Cisco platforms could allow an authenticated, remote attacker to conduct directory traversal attacks and read and write files on the underlying operating system or host system. This vulnerability occurs because the device does not properly validate URIs in IOx API requests. An attacker could exploit this vulnerability by sending a crafted API request that contains directory traversal character sequences to an affected device. A successful exploit could allow the attacker to read or write arbitrary files on the underlying operating system.

  • Published: Mar 24, 2021
  • Updated: Nov 16, 2025
  • CVE: CVE-2021-1385
  • Severity: Medium
  • Exploit:

CVSS v3:

  • Severity: Medium
  • Score: 6.5
  • AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N

CVSS v2:

  • Severity: Medium
  • Score: 6
  • AV:N/AC:M/Au:S/C:P/I:P/A:P
Software From Fixed in
cisco / ios_xe 16.12.1 16.12.1.x
cisco / ios_xe 16.11.1 16.11.1.x
cisco / ios_xe 17.1.1 17.1.1.x
cisco / ios_xe 16.11.1a 16.11.1a.x
cisco / ios_xe 16.12.1c 16.12.1c.x
cisco / ios_xe 16.12.1t 16.12.1t.x
cisco / ios_xe 16.11.2 16.11.2.x
cisco / ios_xe 16.12.1s 16.12.1s.x
cisco / ios_xe 16.12.1a 16.12.1a.x
cisco / ios_xe 16.12.1x 16.12.1x.x
cisco / ios_xe 16.11.1c 16.11.1c.x
cisco / ios_xe 16.11.1b 16.11.1b.x
cisco / ios_xe 16.11.1s 16.11.1s.x
cisco / ios_xe 16.12.1w 16.12.1w.x
cisco / ios_xe 16.12.1y 16.12.1y.x
cisco / ios_xe 16.12.2 16.12.2.x
cisco / ios 15.8(3)m3 15.8(3)m3.x
cisco / ios 15.8(3)m2a 15.8(3)m2a.x
cisco / ios 15.9(3)m 15.9(3)m.x
cisco / ios_xe 16.12.2a 16.12.2a.x
cisco / ios_xe 16.12.4 16.12.4.x
cisco / ios 15.8(3)m4 15.8(3)m4.x
cisco / ios 15.8(3)m5 15.8(3)m5.x
cisco / ios_xe 16.12.3 16.12.3.x
cisco / ios_xe 17.2.1 17.2.1.x
cisco / ios_xe 17.4.1 17.4.1.x
cisco / ios_xe 17.1.1s 17.1.1s.x
cisco / ios_xe 16.12.2t 16.12.2t.x
cisco / ios_xe 17.1.1a 17.1.1a.x
cisco / ios_xe 16.12.2s 16.12.2s.x
cisco / ios_xe 16.12.3a 16.12.3a.x
cisco / ios_xe 17.1.1t 17.1.1t.x
cisco / ios_xe 17.2.1a 17.2.1a.x
cisco / ios_xe 17.2.1v 17.2.1v.x
cisco / ios_xe 16.12.1z 16.12.1z.x
cisco / ios_xe 16.12.3s 16.12.3s.x
cisco / ios_xe 17.2.1r 17.2.1r.x
cisco / ios_xe 17.1.2 17.1.2.x
cisco / ios_xe 16.12.4a 16.12.4a.x
cisco / ios_xe 17.1.3 17.1.3.x
cisco / ios_xe 17.2.2 17.2.2.x
cisco / ios_xe 17.3.1 17.3.1.x
cisco / ios_xe 17.4.1a 17.4.1a.x
cisco / ios_xe 16.12.1za 16.12.1za.x
cisco / ios_xe 17.3.2 17.3.2.x
cisco / ios_xe 17.4.1b 17.4.1b.x
cisco / ios_xe 17.3.1a 17.3.1a.x
cisco / ios_xe 17.3.2a 17.3.2a.x
cisco / ios_xe 17.3.1w 17.3.1w.x
cisco / ios 15.9(3)m2a 15.9(3)m2a.x
cisco / ios 15.9(3)m1 15.9(3)m1.x
cisco / ios 15.9(3)m2 15.9(3)m2.x
cisco / ios_xe 17.3.1x 17.3.1x.x
cisco / ios_xe 16.12.5 16.12.5.x
cisco / ios_xe 16.12.1z1 16.12.1z1.x
cisco / ios 15.8(3)m6 15.8(3)m6.x
cisco / ios 15.9(3)m3 15.9(3)m3.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.