CVE-2021-47955 (GCVE-0-2021-47955)

Vulnerability from cvelistv5 – Published: 2026-05-16 15:26 – Updated: 2026-05-24 01:37
VLAI
Title
CouchCMS 2.2.1 Cross-Site Scripting via SVG File Upload
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.
Severity
5.1 (Medium)
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
5.4 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
References
Impacted products
Vendor Product Version
CouchCMS CouchCMS Affected: 2.2.1
Create a notification for this product.
Date Public
2021-01-25 00:00
Credits
xxcdd
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.