CVE-2021-3988

Public Exploit
Cross-site Scripting (XSS) in janeczku/calibre-web

Description

A Cross-site Scripting (XSS) vulnerability exists in janeczku/calibre-web, specifically in the file `edit_books.js`. The vulnerability occurs when editing book properties, such as uploading a cover or a format. The affected code directly inserts user input into the DOM without proper sanitization, allowing attackers to execute arbitrary JavaScript code. This can lead to various attacks, including stealing cookies. The issue is present in the code handling the `#btn-upload-cover` change event.

Category

6.1
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 3.0 •
EPSS 0.04%
Affected: janeczku janeczku/calibre-web
Published at:
Updated at:

References

Link Tags
https://huntr.com/bounties/fa4c8fd1-7846-4dad-9112-2c07461f0609 exploit
https://github.com/janeczku/calibre-web/commit/7ad419dc8c12180e842a82118f4866ac3d074bc5 patch

Frequently Asked Questions

What is the severity of CVE-2021-3988?
CVE-2021-3988 has been scored as a medium severity vulnerability.
How to fix CVE-2021-3988?
To fix CVE-2021-3988, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-3988 being actively exploited in the wild?
It is possible that CVE-2021-3988 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-3988?
CVE-2021-3988 affects janeczku janeczku/calibre-web.
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