Cyber Resilience

CVE-2025-20140

Cisco Ios Xe 16.10.1 … 17.9.5f

Published
07 May 2025
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 0.0024 15th percentile
Risk Priority 53 floored blend · peak EPSS

Summary

CVE-2025-20140 is a high-severity Memory Allocation with Excessive Size Value (CWE-789) vulnerability in Cisco Ios Xe. Its CVSS base score is 7.4 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Endpoint Denial of Service (T1499); ranked at the 15th 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 SI-10 (Information Input Validation) and SC-6 (Resource Availability) — see the control section below for these in your framework.

EU & UK References

Vulnerability Data

A vulnerability in the Wireless Network Control daemon (wncd) of Cisco IOS XE Software for Wireless LAN Controllers (WLCs) could allow an unauthenticated, adjacent wireless attacker to cause a denial of service (DoS) condition. This vulnerability is due to improper…

more

memory management. An attacker could exploit this vulnerability by sending a series of IPv6 network requests from an associated wireless IPv6 client to an affected device. To associate a client to a device, an attacker may first need to authenticate to the network, or associate freely in the case of a configured open network. A successful exploit could allow the attacker to cause the wncd process to consume available memory and eventually cause the device to stop responding, resulting in a DoS condition.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1499 Endpoint Denial of Service Impact
Adversaries may perform Endpoint Denial of Service (DoS) attacks to degrade or block the availability of services to users.
T1499.003 Application Exhaustion Flood Impact
Adversaries may target resource intensive features of applications to cause a denial of service (DoS), denying availability to those applications.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-20202Same product: Cisco Catalyst 9800-40
CVE-2025-20165Same vendor: Cisco
CVE-2024-20303Same product: Cisco Catalyst 9105Axi
CVE-2025-20190Same product: Cisco Catalyst 9105Axi
CVE-2023-20089Same vendor: Cisco
CVE-2026-20106Same vendor: Cisco
CVE-2026-20105Same vendor: Cisco
CVE-2026-20014Same vendor: Cisco
CVE-2026-20015Same vendor: Cisco
CVE-2026-20021Same vendor: Cisco

Affected Assets

cisco
ios xe
16.10.1, 16.10.1a, 16.10.1b, 16.10.1c, 16.10.1d

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

Input validation directly rejects or bounds untrusted size values before any allocation occurs.

Resource quotas and priority allocation limit the system-wide impact of an oversized request.

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 SDLC practices directly prevent coding flaws that trust unvalidated size values for allocations.

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 in development can detect and block excessive allocation flaws before deployment.

prevents

Secure development lifecycle includes input validation and size checks that prevent unbounded allocations.

prevents

Application security requirements mandate bounds checking on size parameters to avoid excessive memory allocation.

prevents

Secure architecture principles require resource-limit enforcement that mitigates uncontrolled memory requests.

prevents

Secure coding standards directly prohibit allocating memory from untrusted size values without validation.

none

Capacity management monitors overall resource use but does not prevent individual allocation bugs.

References