CVE-2021-21004
Cross-site Scripting Vulnerability in Phoenix Contact FL SWITCH SMCS series products
In Phoenix Contact FL SWITCH SMCS series products in multiple versions an attacker may insert malicious code via LLDP frames into the web-based management which could then be executed by the client.
Attack profile
How easy it is to exploit
- Attack vector
- Adjacent network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- Low
- Integrity
- High
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Cross-site Scripting Vulnerability in Phoenix Contact FL SWITCH SMCS series products
In Phoenix Contact FL SWITCH SMCS series products in multiple versions an attacker may insert malicious code via LLDP frames into the web-based management which could then be executed by the client.
- Record
CVE-2021-21004- CVSS 3.1
- 7.4 High
CVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:C/C:L/I:H/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
EUVDEUVD-2021-8413
In Phoenix Contact FL SWITCH SMCS series products in multiple versions an attacker may insert malicious code via LLDP frames into the web-based management which could then be executed by the client.
- Record
EUVD-2021-8413- CVSS 3.1
- 7.4 High
CVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:C/C:L/I:H/A:N - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-p92q-6vw3-958m No score
In Phoenix Contact FL SWITCH SMCS series products in multiple versions an attacker may insert...
In Phoenix Contact FL SWITCH SMCS series products in multiple versions an attacker may insert malicious code via LLDP frames into the web-based management which could then be executed by the client.
- Record
GHSA-p92q-6vw3-958m- Weakness
- CWE-79
- Updated
- 2026-11-02
NVD
In Phoenix Contact FL SWITCH SMCS series products in multiple versions an attacker may insert malicious code via LLDP frames into the web-based management which could then be executed by the client.
- Record
CVE-2021-21004- CVSS 3.1
- 7.4 High
CVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:C/C:L/I:H/A:N - CVSS 3.1
- 6.1 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - CVSS 2.0
- 4.3 Medium
AV:N/AC:M/Au:N/C:N/I:P/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
Affected products
- phoenix contact fl switch
- phoenix contact fl nat
- phoenixcontact fl nat smn 8tx-m firmware
- phoenixcontact fl nat smn 8tx firmware
- phoenixcontact fl switch smcs 14tx\/2fx-sm firmware
- phoenixcontact fl switch smcs 14tx\/2fx firmware
- phoenixcontact fl switch smcs 16tx firmware
- phoenixcontact fl switch smcs 4tx-pn firmware
- phoenixcontact fl switch smcs 6gt\/2sfp firmware
- phoenixcontact fl switch smcs 6tx\/2sfp firmware
- phoenixcontact fl switch smcs 8gt firmware
- phoenixcontact fl switch smcs 8tx-pn firmware
History
| Recorded | Changed | Sources |
|---|---|---|
| facts | ||
| aliases, published | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-21004 is a high vulnerability (CVSS 7.4) in Phoenix Contact Fl Switch, published June 25, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.58%, the 48th percentile. No source names a fixed version.