CVE-2021-3646 json
Cross-site Scripting (XSS) - Reflected in btcpayserver/btcpayserver
published 2021-09-10 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-26943
- cvss
- 4.9
- version 3.0, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.8%
- EPSS 0.8% chance of exploitation in 30 days, percentile 55%
- public exploits
- 0
- none known
Summary
btcpayserver is vulnerable to Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Patch / fix
Exploit prediction
0.77% chance of exploitation in the next 30 days, higher than 55% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- huntr.dev https://huntr.dev/bounties/32e30ecf-31fa-45f6-8552-47250ef0e613 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.0 | 4.9 | CVSS:3.0/AV:A/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:L |
| 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
- btcpayserver btcpayserver/btcpayserver
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
-
github.com
/btcpayserver/btcpayserver/commit/fc4e47cec608cc3dba24b19d0145ac69320b975e
patch, third-party-advisory
-
huntr.dev
/bounties/32e30ecf-31fa-45f6-8552-47250ef0e613
exploit, third-party-advisory
Sources
- CVE List CVE-2021-3646
- NVD CVE-2021-3646
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