CVE-2021-20680

Name: CVE-2021-20680
Creator: NVD / NIST
Published: 2021-04-26T01:15:07.77+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.1/10EPSS 0.80%

Last modified Jun 17, 2026

CVE-2021-20680 is a medium-severity vulnerability rated 6.1/10 on the CVSS scale. Cross-site scripting vulnerability in NEC Aterm devices (Aterm WG1900HP2 firmware Ver.1.3.1 and earlier, Aterm WG1900HP firmware Ver.2.5.1 and earlier, Aterm WG1800HP4 firmware Ver.1.3.1 and earlier, Aterm WG1800HP3 firmware Ver.1.5.1 and earlier, Aterm WG1200HS2 firmware Ver.2.5.0 and earlier, Aterm WG1200HP3 firmware Ver.1.3.1 and earlier, Aterm WG1200HP2 firmware Ver.2.5.0 and earlier, Aterm W1200EX firmware Ver.1.3.1 and earlier, Aterm W1200EX-MS firmware Ver.1.3.1 and earlier, Aterm WG1200HS firmware all versions Aterm WG1200HP firmware all versions Aterm WF800HP firmware all versions Aterm WF300HP2 firmware all versions Aterm WR8165N firmware all versions Aterm W500P firmware all versions, and Aterm W300P firmware all versions) allows remote attackers to inject arbitrary script or HTML via unspecified vectors.. EPSS estimates a 0.80% chance of exploitation in the next 30 days.

Description

Cross-site scripting vulnerability in NEC Aterm devices (Aterm WG1900HP2 firmware Ver.1.3.1 and earlier, Aterm WG1900HP firmware Ver.2.5.1 and earlier, Aterm WG1800HP4 firmware Ver.1.3.1 and earlier, Aterm WG1800HP3 firmware Ver.1.5.1 and earlier, Aterm WG1200HS2 firmware Ver.2.5.0 and earlier, Aterm WG1200HP3 firmware Ver.1.3.1 and earlier, Aterm WG1200HP2 firmware Ver.2.5.0 and earlier, Aterm W1200EX firmware Ver.1.3.1 and earlier, Aterm W1200EX-MS firmware Ver.1.3.1 and earlier, Aterm WG1200HS firmware all versions Aterm WG1200HP firmware all versions Aterm WF800HP firmware all versions Aterm WF300HP2 firmware all versions Aterm WR8165N firmware all versions Aterm W500P firmware all versions, and Aterm W300P firmware all versions) allows remote attackers to inject arbitrary script or HTML via unspecified vectors.

Metrics

CVSS 3.1

6.1/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

EPSS Probability

0.80%

51.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-79

Affected Software

Vendor	Product	Versions
Nec	Aterm Wg1900hp2 Firmware	<= 1.3.1
Nec	Aterm Wg1900hp Firmware	<= 2.5.1
Nec	Aterm Wg1800hp4 Firmware	<= 1.3.1
Nec	Aterm Wg1800hp3 Firmware	<= 1.5.1
Nec	Aterm Wg1200hs3 Firmware	<= 1.1.2
Nec	Aterm Wg1200hs2 Firmware	<= 2.5.0
Nec	Aterm Wg1200hp3 Firmware	<= 1.3.1
Nec	Aterm Wg1200hp2 Firmware	<= 2.5.0
Nec	Aterm W1200ex Firmware	<= 1.3.1
Nec	Aterm W1200ex-Ms Firmware	<= 1.3.1
Nec	Aterm Wg1200hs Firmware	All versions
Nec	Aterm Wg1200hp Firmware	All versions
Nec	Aterm Wf800hp Firmware	All versions
Nec	Aterm Wf300hp2 Firmware	All versions
Nec	Aterm Wr8165n Firmware	All versions
Nec	Aterm W500p Firmware	All versions
Nec	Aterm W300p Firmware	All versions

References

https://jpn.nec.com/security-info/secinfo/nv21-008.htmlVendor Advisory
https://jvn.jp/en/jp/JVN67456944/index.htmlThird Party Advisory
https://jpn.nec.com/security-info/secinfo/nv21-008.htmlVendor Advisory
https://jvn.jp/en/jp/JVN67456944/index.htmlThird Party Advisory

Timeline

Published: Apr 26, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-20680?

How severe is CVE-2021-20680?

CVE-2021-20680 has a CVSS score of 6.1/10 (MEDIUM severity). The EPSS model estimates a 0.80% probability of exploitation in the next 30 days.

How do I fix CVE-2021-20680?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-20680?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST