CVE-2021-3646

mediumpriority · track · 24EPSS 0.008 · 55 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.77% (55th) EPSS

CVSS 4.3 · medium

Is it mine?

2 products

Who says so?

3 sources

cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-27

btcpayserver is vulnerable to Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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

v3.04.9mediumCVSS:3.0/AV:A/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:Lsecondary · ENISA EU

v3.04.9mediumCVSS:3.0/AV:A/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:Lsecondary · security@huntr.devexploitability 1.5 · impact 3.4

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)

The CWE weakness classes this flaw belongs to.

Products and version ranges known to be affected.

Other names and identifiers for this entity.

Which sources assert this record, and when.

published 2021-09-10modified 2026-06-17

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External citations — patches, advisories, analysis.

scry

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