CVE-2021-3986: calibre-web Information Disclosure

Description

A vulnerability in janeczku/calibre-web allows unauthorized users to view the names of private shelves belonging to other users. This issue occurs in the file shelf.py at line 221, where the name of the shelf is exposed in an error message when a user attempts to remove a book from a shelf they do not own. This vulnerability discloses private information and affects all versions prior to the fix.

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CVSS v3.1 Score

4.3

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

Weakness Type (CWE)

CWE-209 CWE-209

Affected Products

Vendor	Product	Versions
janeczku	calibre-web	< 0.6.15

References

Advisories & Patches

https://github.com/janeczku/calibre-web/commit/6f5390ead5df9779ac81fadefffb476e03f93548 https://huntr.com/bounties/394af194-61a7-4e33-b373-877d4c766fca

Exploits

https://huntr.com/bounties/394af194-61a7-4e33-b373-877d4c766fca

Frequently Asked Questions

What is CVE-2021-3986? +

A vulnerability in janeczku/calibre-web allows unauthorized users to view the names of private shelves belonging to other users. This issue occurs in the file shelf.py at line 221, where the name of the shelf is exposed in an error message when a user attempts to remove a book from a shelf they do not own. This vulnerability discloses private information and affects all versions prior to the fix. It has a CVSS v3.1 base score of 4.3 (MEDIUM).

How severe is CVE-2021-3986? +

CVE-2021-3986 has a CVSS v3.1 score of 4.3 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2021-3986? +

CVE-2021-3986 affects products from janeczku, specifically: calibre-web. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2021-3986? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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CVE-2021-3986