Описание
changedetection.io: Stored XSS in Watch update via API
Summary
A Stored Cross Site Scripting is present in the changedetection.io Watch update API due to unsufficient security checks.
Details
Tested on changedetection.io version v0.50.24
When a user tries to add an unsafe URL as a Watch in the changedetection.io UI, the action is blocked with the error message "Watch protocol is not permitted by SAFE_PROTOCOL_REGEX or incorrect URL format".
This is catched by the function validate_url(test_url).
When instead the Watch API is used, this check is not performed resulting in unsafe URLs added as Watch.
PoC
Update an existing watch with an unsafe URL
Impact
Two scenarios are possibile:
- An attacker can insert a new watch with an arbitrary URL which really points to a web page. Once the HTML content is retrieved, the attacker updates the URL with a JavaScript payload.
- An attacker substitutes the URL in an existing watch with a new URL that is in reality a JavaScript payload.
When the user clicks on Preview and then on the malicious link, the JavaScript malicious code is executed.
Credits
Edoardo Ottavianelli @edoardottt
Ссылки
- https://github.com/dgtlmoon/changedetection.io/security/advisories/GHSA-4c3j-3h7v-22q9
- https://nvd.nist.gov/vuln/detail/CVE-2025-62780
- https://github.com/dgtlmoon/changedetection.io/issues/3562
- https://github.com/dgtlmoon/changedetection.io/pull/3564
- https://github.com/dgtlmoon/changedetection.io/releases/tag/0.50.34
Пакеты
changedetection.io
< 0.50.34
0.50.34
Связанные уязвимости
changedetection.io is a free open source web page change detection tool. A Stored Cross Site Scripting is present in changedetection.io Watch update API in versions prior to 0.50.34 due to insufficient security checks. Two scenarios are possible. In the first, an attacker can insert a new watch with an arbitrary URL which really points to a web page. Once the HTML content is retrieved, the attacker updates the URL with a JavaScript payload. In the second, an attacker substitutes the URL in an existing watch with a new URL that is in reality a JavaScript payload. When the user clicks on *Preview* and then on the malicious link, the JavaScript malicious code is executed. Version 0.50.34 fixes the issue.