Cyber Resilience

CVE-2024-20303

Cisco Ios Xe 17.10.1 … 17.9.3a

Published
27 March 2024
Modified
17 June 2026
Patch / advisory
CVSS Score v3.1 7.4
Click a component to see what it means
Raw vectorCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
EPSS Score 0.0032 25th percentile
Risk Priority 53 floored blend · peak EPSS

Summary

CVE-2024-20303 is a high-severity Incomplete Cleanup (CWE-459) vulnerability in Cisco Ios Xe. Its CVSS base score is 7.4 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Data from Local System (T1005); ranked at the 25th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SI-14 (Non-persistence) — see the control section below for these in your framework.

EU & UK References

Vulnerability Data

A vulnerability in the multicast DNS (mDNS) gateway feature of Cisco IOS XE Software for Wireless LAN Controllers (WLCs) could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition. This vulnerability is due to improper management…

more

of mDNS client entries. An attacker could exploit this vulnerability by connecting to the wireless network and sending a continuous stream of specific mDNS packets. A successful exploit could allow the attacker to cause the wireless controller to have high CPU utilization, which could lead to access points (APs) losing their connection to the controller and result in a DoS condition.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1005 Data from Local System Collection
Adversaries may search local system sources, such as file systems, configuration files, local databases, virtual machine files, or process memory, to find files of interest and sensitive data prior to Exfiltration.
T1552 Unsecured Credentials Credential Access
Adversaries may search compromised systems to find and obtain insecurely stored credentials.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-20190Same product: Cisco Catalyst 9105Axi
CVE-2025-20140Same product: Cisco Catalyst 9105Axi
CVE-2025-2260Shared CWE-459
CVE-2024-36353Shared CWE-459
CVE-2026-34263Shared CWE-459
CVE-2024-26756Shared CWE-459
CVE-2025-6338Shared CWE-459
CVE-2025-0032Shared CWE-459
CVE-2025-37908Shared CWE-459
CVE-2023-20077Same vendor: Cisco

Affected Assets

cisco
ios xe
17.10.1, 17.10.1a, 17.10.1b, 17.11.1, 17.11.1a

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)
  • V6.4.1

Mitigating Controls (NIST 800-53 r5) AI

Developer testing and evaluation can discover incomplete cleanup through dynamic analysis or resource-leak testing.

Non-persistence mechanisms explicitly initiate resources in a known state and terminate them, directly enforcing cleanup.

Session termination forces explicit release of session-related temporary resources.

Preventing unintended information transfer through shared resources requires complete cleanup of those resources.

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

Secure-development practices and coding standards normally require proper resource release and cleanup.

ID.AM-08 partial match
prevents

Life-cycle management encompasses disposal of temporary resources but does not specifically target runtime cleanup bugs.

PR.DS-10 partial match
prevents

Explicitly calls for removing sensitive data after use, directly addressing one class of incomplete cleanup.

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.

degrades

Explicitly requires secure deletion of temporary or residual data, directly addressing incomplete cleanup.

prevents

SDLC practices include cleanup steps, yet the weakness can still occur if those steps are omitted.

prevents

Secure-coding rules can mandate explicit cleanup of temporary resources, but do not guarantee it.

finds

Change-management processes may require cleanup verification, but the control itself does not address the weakness.

References