WAGO: Managed Switches: Reflected Cross-site Scripting

published 2021-05-13 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-8403

cvss: 8.8; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.6%; EPSS 0.6% chance of exploitation in 30 days, percentile 50%
public exploits: 0; none known

In multiple managed switches by WAGO in different versions an attacker may trick a legitimate user to click a link to inject possible malicious code into the Web-Based Management.

Exploit prediction

0.63% chance of exploitation in the next 30 days, higher than 50% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	8.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
NVD	3.1	6.1	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
NVD	2.0	4.3	AV:N/AC:M/Au:N/C:N/I:P/A:N

Affected products

WAGO 0852-0303
WAGO 0852-1305
WAGO 0852-1505
WAGO 0852-1305/000-001
WAGO 0852-1505/000-001

Classification

Weakness

CWE-79 Improper Neutralization of Input During Web Page Generation

References

cert.vde.com /en-us/advisories/vde-2021-013
third-party-advisory

Sources

CVE List CVE-2021-20994
NVD CVE-2021-20994

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary