Cisco IOS XE Wireless Controller Software for the Catalyst 9000 Family Stored Cross-Site Scripting Vulnerability

published 2021-03-24 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-6841

cvss: 4.8; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.7%; EPSS 0.7% chance of exploitation in 30 days, percentile 51%
public exploits: 0; none known

A vulnerability in the web-based management interface of Cisco IOS XE Wireless Controller software for the Catalyst 9000 Family of switches could allow an authenticated, remote attacker to conduct a cross-site scripting (XSS) attack against another user of the web-based management interface of an affected device. The vulnerability is due to insufficient validation of user-supplied input by the web-based management interface of an affected device. An attacker could exploit this vulnerability by authenticating to the device as a high-privileged user, adding certain configurations with malicious code in one of its fields, and persuading another user to click on it. A successful exploit could allow the attacker to execute arbitrary script code in the context of the affected interface or to access sensitive, browser-based information.

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 2 y ago (2024-11-08)

Exploit prediction

0.66% chance of exploitation in the next 30 days, higher than 51% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	4.8	CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N
NVD	3.1	4.8	CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N
NVD	2.0	3.5	AV:N/AC:M/Au:S/C:N/I:P/A:N

Affected products

Cisco Cisco IOS XE Software

Classification

Weakness

CWE-79 Improper Neutralization of Input During Web Page Generation

Technology feeds

Cisco IOS rss critical rss

References

tools.cisco.com /security/center/content/CiscoSecurityAdvisory/cisco-sa-ewlc-xss-cAfMtCzv
vendor-advisory

Sources

CVE List CVE-2021-1374
NVD CVE-2021-1374

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Summary