CVE-2021-20680

mediumpriority · track · 24EPSS 0.008 · 56 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.80% (56th) EPSS

CVSS 4.3 · medium

Is it mine?

18 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-28

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.

cvss

Technical severity, 0–10. One row per scoring source.

6.1

010

base score 0–10 · higher = more severe · hover a vector to decode

v2.04.3mediumAV:N/AC:M/Au:N/C:N/I:P/A:Nprimary · NVD / NIST USexploitability 8.6 · impact 2.9

v3.16.1mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:Nprimary · NVD / NIST USexploitability 2.8 · impact 2.7

v3.15.6mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-79USprimary

affected products (18)

Products and version ranges known to be affected.

NEC Corporation 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 versionsenisa_euvdEU
nec aterm w1200ex firmware≤ 1.3.1nvdUScpe:2.3:o:nec:aterm_w1200ex_firmware:*:*:*:*:*:*:*:*
nec aterm w1200ex-ms firmware≤ 1.3.1nvdUScpe:2.3:o:nec:aterm_w1200ex-ms_firmware:*:*:*:*:*:*:*:*
nec aterm w300p firmwareall versionsnvdUScpe:2.3:o:nec:aterm_w300p_firmware:*:*:*:*:*:*:*:*
nec aterm w500p firmwareall versionsnvdUScpe:2.3:o:nec:aterm_w500p_firmware:*:*:*:*:*:*:*:*
nec aterm wf300hp2 firmwareall versionsnvdUScpe:2.3:o:nec:aterm_wf300hp2_firmware:*:*:*:*:*:*:*:*
nec aterm wf800hp firmwareall versionsnvdUScpe:2.3:o:nec:aterm_wf800hp_firmware:*:*:*:*:*:*:*:*
nec aterm wg1200hp firmwareall versionsnvdUScpe:2.3:o:nec:aterm_wg1200hp_firmware:*:*:*:*:*:*:*:*
nec aterm wg1200hp2 firmware≤ 2.5.0nvdUScpe:2.3:o:nec:aterm_wg1200hp2_firmware:*:*:*:*:*:*:*:*
nec aterm wg1200hp3 firmware≤ 1.3.1nvdUScpe:2.3:o:nec:aterm_wg1200hp3_firmware:*:*:*:*:*:*:*:*
nec aterm wg1200hs firmwareall versionsnvdUScpe:2.3:o:nec:aterm_wg1200hs_firmware:*:*:*:*:*:*:*:*
nec aterm wg1200hs2 firmware≤ 2.5.0nvdUScpe:2.3:o:nec:aterm_wg1200hs2_firmware:*:*:*:*:*:*:*:*
nec aterm wg1200hs3 firmware≤ 1.1.2nvdUScpe:2.3:o:nec:aterm_wg1200hs3_firmware:*:*:*:*:*:*:*:*
nec aterm wg1800hp3 firmware≤ 1.5.1nvdUScpe:2.3:o:nec:aterm_wg1800hp3_firmware:*:*:*:*:*:*:*:*
nec aterm wg1800hp4 firmware≤ 1.3.1nvdUScpe:2.3:o:nec:aterm_wg1800hp4_firmware:*:*:*:*:*:*:*:*
nec aterm wg1900hp firmware≤ 2.5.1nvdUScpe:2.3:o:nec:aterm_wg1900hp_firmware:*:*:*:*:*:*:*:*
nec aterm wg1900hp2 firmware≤ 1.3.1nvdUScpe:2.3:o:nec:aterm_wg1900hp2_firmware:*:*:*:*:*:*:*:*
nec aterm wr8165n firmwareall versionsnvdUScpe:2.3:o:nec:aterm_wr8165n_firmware:*:*:*:*:*:*:*:*

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd NVD CVE.org MITRE

published 2021-04-26modified 2026-06-17

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+53087 more

references (8)

External citations — patches, advisories, analysis.

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