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Status published
Medium
CVE-2021-29438
Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS) in @nextcloud/dialogs
Vulnerability Description
The Nextcloud dialogs library (npm package @nextcloud/dialogs) before 3.1.2 insufficiently escaped text input passed to a toast. If your application displays toasts with user-supplied input, this could lead to a XSS vulnerability. The vulnerability has been patched in version 3.1.2 If you need to display HTML in the toast, explicitly pass the `options.isHTML` config flag.
Impact Analysis
Refer to official advisory for detailed impact metrics.
Remediation
Ensure systems are updated to the latest vendor-supplied patch levels.
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Credits & Attribution
No credits recorded in the NVD database.
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Affected Vendor
nextcloud
View all reports →Affected Software
nextcloud-dialogs
Vulnerable Versions:
< 3.1.2
Timeline
Official Publish:
April 13th, 2021
Last Modified:
August 3rd, 2024
Added to House:
July 21st, 2026
CVSS Vectors
V3:
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N
MITRE ATT&CK TTPs
T1189
Drive-by Compromise
Initial Access
T1059.007
JavaScript
Execution
T1539
Steal Web Session Cookie
Collection
T1213
Data from Information Repositories
Collection
T1567
Exfiltration Over Web Service
Exfiltration
T1491.001
Defacement
Impact
T1059
Command and Scripting Interpreter
Execution
T1552
Unsecured Credentials
Credential Access
T1071
Application Layer Protocol
Command and Control
T1565
Data Manipulation
Impact