Stored XSS due to Unrestricted File Upload in star7th/showdoc


Reported on

Mar 13th 2022


Stored XSS via uploading files in .xsl format.

Proof of Concept


<a:script xmlns:a="">alert(1)</a:script>

Steps to Reproduce

1.Login into
2.Navigate to file library (
3.In the File Library page, click the Upload button and choose the poc.xsl file.
4.After uploading the file, click on the check button to open that file in a new tab.

XSS will trigger when the attachment is opened in a new tab.



An attacker can perform social engineering on users by redirecting them from a real website to a fake one. a hacker can steal their cookies etc.

We are processing your report and will contact the star7th/showdoc team within 24 hours. a year ago
Ajaysen R modified the report
a year ago
Ajaysen R submitted a
a year ago
star7th validated this vulnerability a year ago
Ajaysen R has been awarded the disclosure bounty
The fix bounty is now up for grabs
star7th marked this as fixed in v2.10.4 with commit 4b6e66 a year ago
Ajaysen R has been awarded the fix bounty
This vulnerability will not receive a CVE
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