Cyber Resilience

CVE-2023-20273

RCE in Cisco Ios Xe 17.3 – 17.3.8a

CISA KEVActive ExploitationEUVD ExploitedRCECommand Injection
Published
25 October 2023
Modified
28 October 2025
KEV Added
23 October 2023
Patch / advisory
CVSS Score v3.1 7.2
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.90 99.8th percentile
Risk Priority 79 floored blend · peak EPSS

Summary

CVE-2023-20273 is a high-severity OS Command Injection (CWE-78) vulnerability in Cisco Ios Xe. Its CVSS base score is 7.2 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Command and Scripting Interpreter (T1059); ranked in the top 0.2% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2023-20273 is a command injection vulnerability in the web UI feature of Cisco IOS XE Software that stems from insufficient input validation and is tracked under CWE-78. Successful exploitation permits an attacker to execute arbitrary commands on the underlying operating system with root privileges. The flaw carries a CVSS 3.1 base score of 7.2 and affects the web UI component across supported IOS XE releases.

An authenticated remote attacker with valid administrative credentials can exploit the issue by submitting specially crafted input through the web UI. This grants the attacker the ability to run commands at root level on the device, potentially leading to full control of the affected system including configuration changes, data exfiltration, or persistence mechanisms.

The official Cisco Security Advisory cisco-sa-iosxe-webui-privesc-j22SaA4z details the affected versions and available software updates that address the vulnerability. The flaw is also listed in CISA's Known Exploited Vulnerabilities catalog, indicating that federal agencies and other organizations should prioritize patching according to the published timelines.

The EPSS score for this CVE currently stands at 0.9262 with a recorded peak of 0.9265, reflecting sustained high exploitation interest since disclosure.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

A vulnerability in the web UI feature of Cisco IOS XE Software could allow an authenticated, remote attacker to inject commands with the privileges of root. This vulnerability is due to insufficient input validation. An attacker could exploit this vulnerability…

more

by sending crafted input to the web UI. A successful exploit could allow the attacker to inject commands to the underlying operating system with root privileges.

CWE(s)
KEV Date Added
23 October 2023

Related Threats

MITRE ATT&CK Enterprise Techniques

T1059 Command and Scripting Interpreter Execution
Adversaries may abuse command and script interpreters to execute commands, scripts, or binaries.
T1059.003 Windows Command Shell Execution
Adversaries may abuse the Windows command shell for execution.
T1059.004 Unix Shell Execution
Adversaries may abuse Unix shell commands and scripts for execution.
T1059.001 PowerShell Execution
Adversaries may abuse PowerShell commands and scripts for execution.
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2024-20399Same vendor: Ciscoboth on KEV
CVE-2021-1497Same vendor: Ciscoboth on KEV
CVE-2019-1652Same vendor: Ciscoboth on KEV
CVE-2022-20708Same vendor: Ciscoboth on KEV
CVE-2025-20186Same product: Cisco Ios Xe
CVE-2025-20193Same product: Cisco Ios Xe
CVE-2025-20194Same product: Cisco Ios Xe
CVE-2017-12240Same product: Cisco Catalyst 3650both on KEV
CVE-2023-20082Same product: Cisco Ios Xe
CVE-2023-20056Same product: Cisco Ios Xe

Affected Assets

cisco
ios xe
16.1.1, 16.1.2, 16.1.3, 16.10.1, 16.10.1a · 17.3 — 17.3.8a · 17.6 — 17.6.6a · 17.9 — 17.9.4a

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V1.2.5
  • V1.2.8
  • V15.2.5

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-78

Platform-independent apps typically execute inside a managed runtime or sandbox that restricts direct OS command execution, reducing the ability to exploit OS command injection.

addresses: CWE-78

Validates inputs to block special elements that would alter OS command execution.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

PR.PS-06's SDLC practices directly require secure coding and input handling that blocks command-injection defects, yet the single broad outcome leaves many specific neutralization vectors and verification gaps unaddressed.

PR.PS-02 partial match
prevents

Routine patching/maintenance can remediate known command-injection CVEs in dependencies (partial forward) but does nothing to stop developers from introducing improper neutralization in custom code (none reverse).

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Security testing and code review target insecure use of operating-system command interfaces, catching command-injection flaws introduced during development.

References