CVE-2021-34815 json
CheckSec Canopy before 3.5.2 allows XSS attacks against the login page via the LOGIN_PAGE_DISCLAIMER parameter.
published 2021-06-18 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-21462
- cvss
- 4.8
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.8%
- EPSS 0.8% chance of exploitation in 30 days, percentile 57%
- public exploits
- 0
- none known
Summary
CheckSec Canopy before 3.5.2 allows XSS attacks against the login page via the LOGIN_PAGE_DISCLAIMER parameter.
Patch / fix
- checksec canopy 3.5.2
Exploit prediction
0.84% chance of exploitation in the next 30 days, higher than 57% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- compass-security.com https://www.compass-security.com/fileadmin/Research/Advisories/2021-10_CSNC-2021-015-Checksec_Canopy_HTLM_Injection.txt referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 4.8 | CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N |
| NVD | 2.0 | 3.5 | AV:N/AC:M/Au:S/C:N/I:P/A:N |
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
-
compass-security.com
/fileadmin/Research/Advisories/2021-10_CSNC-2021-015-Checksec_Canopy_HTLM_Injection.txt
exploit, third-party-advisory
-
checksec.com
/canopy.html
product
-
compass-security.com
/en/research/advisories
third-party-advisory
Sources
- CVE List CVE-2021-34815
- NVD CVE-2021-34815
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