CVE-2021-3758

Name: CVE-2021-3758
Creator: NVD / NIST
Published: 2021-09-02T12:15:07.693+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.5/10EPSS 0.77%

Last modified Jun 17, 2026

CVE-2021-3758 is a medium-severity vulnerability rated 6.5/10 on the CVSS scale. bookstack is vulnerable to Server-Side Request Forgery (SSRF). EPSS estimates a 0.77% chance of exploitation in the next 30 days.

Description

bookstack is vulnerable to Server-Side Request Forgery (SSRF)

Metrics

CVSS 3.1

6.5/10

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

EPSS Probability

0.77%

51.1th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Bookstackapp	Bookstack	< 21.08

References

https://github.com/bookstackapp/bookstack/commit/bee5e2c7ca637d034c6985c0328cef0ce068778ePatch, Third Party Advisory
https://huntr.dev/bounties/a8d7fb24-9a69-42f3-990a-2db93b53f76bExploit, Issue Tracking, Third Party Advisory
https://github.com/bookstackapp/bookstack/commit/bee5e2c7ca637d034c6985c0328cef0ce068778ePatch, Third Party Advisory
https://huntr.dev/bounties/a8d7fb24-9a69-42f3-990a-2db93b53f76bExploit, Issue Tracking, Third Party Advisory

Timeline

Published: Sep 2, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-3758?

bookstack is vulnerable to Server-Side Request Forgery (SSRF)

How severe is CVE-2021-3758?

CVE-2021-3758 has a CVSS score of 6.5/10 (MEDIUM severity). The EPSS model estimates a 0.77% probability of exploitation in the next 30 days.

How do I fix CVE-2021-3758?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-3758?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST