CVE-2021-3987: calibre-web Access Control Flaw

Description

An improper access control vulnerability exists in janeczku/calibre-web. The affected version allows users without public shelf permissions to create public shelves. The vulnerability is due to the `create_shelf` method in `shelf.py` not verifying if the user has the necessary permissions to create a public shelf. This issue can lead to unauthorized actions being performed by users.

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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:N/I:L/A:N

Weakness Type (CWE)

CWE-284 CWE-284

CWE-862 Missing Authorization

Affected Products

Vendor	Product	Versions
janeczku	calibre-web	< 0.6.15

References

Advisories & Patches

https://github.com/janeczku/calibre-web/commit/bcdc97641447965af486964537f3821f47b28874

Exploits

https://huntr.com/bounties/29fcc091-87b6-43bc-ab4b-3c0bec3f71df

Frequently Asked Questions

What is CVE-2021-3987? +

An improper access control vulnerability exists in janeczku/calibre-web. The affected version allows users without public shelf permissions to create public shelves. The vulnerability is due to the `create_shelf` method in `shelf.py` not verifying if the user has the necessary permissions to create a public shelf. This issue can lead to unauthorized actions being performed by users. It has a CVSS v3.1 base score of 4.3 (MEDIUM).

How severe is CVE-2021-3987? +

CVE-2021-3987 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-2021-3987? +

CVE-2021-3987 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-2021-3987? +

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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