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PYSEC-2026-1243
No affected components available
Summary
Input in parameter notification_urls is not processed resulting in javascript execution in the application
Details
changedetection.io version: v0.45.21
https://github.com/dgtlmoon/changedetection.io/blob/0.45.21/changedetectionio/forms.py#L226
for server_url in field.data:
if not apobj.add(server_url):
message = field.gettext('\'%s\' is not a valid AppRise URL.' % (server_url))
raise ValidationError(message)
PoC
Setting > ADD Notification URL List
"><img src=x onerror=alert(document.domain)>
Requests
Impact
A reflected XSS vulnerability happens when the user input from a URL or POST data is reflected on the page without being stored, thus allowing the attacker to inject malicious content
The vulnerability can be exploited over the network without needing physical access. It is easy for an attacker to exploit this vulnerability. An attacker does not need any special privileges or access rights. The attacker needs the user to perform some action, like clicking a link. The impact is confined to the system where the vulnerability exists. There is a low impact on the integrity of the data.
Exploitation attempts have been detected. Elevated vigilance and prompt remediation are advised.
The exploit probability is very low. The vulnerability is unlikely to be exploited in the next 30 days.
We did not find any exploit available. Neither in GitHub repositories nor in the Exploit-Database.
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