CVE-2021-47955 json
CouchCMS 2.2.1 Cross-Site Scripting via SVG File Upload
published 2026-05-16 5 mo ago modified 2026-06-17 4 mo ago also EUVD-2021-34823
- cvss
- 5.4
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 6%
- public exploits
- 0
- none known
Summary
CouchCMS 2.2.1 contains a cross-site scripting vulnerability that allows authenticated attackers to execute arbitrary JavaScript by uploading malicious SVG files through the file upload functionality. Attackers can upload SVG files containing embedded script tags to the browse.php endpoint, which are then executed in users' browsers when the files are accessed or previewed.
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- partial
- Assessed
- 5 mo ago
Exploit prediction
0.17% chance of exploitation in the next 30 days, higher than 6% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- exploit-db.com https://www.exploit-db.com/exploits/49636 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 5.1 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N |
| CNA | 3.1 | 5.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N |
| CNA | 4.0 | 5.1 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Affected products
- CouchCMS CouchCMS
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
-
exploit-db.com
/exploits/49636
exploit
-
github.com
/CouchCMS/CouchCMS
product
-
vulncheck.com
/advisories/couchcms-cross-site-scripting-via-svg-file-upload
third-party-advisory
Sources
- CVE List CVE-2021-47955
- NVD CVE-2021-47955
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