CVE-2024-21500

Name: CVE-2024-21500
Creator: NVD / NIST
Published: 2024-02-17T05:15:10.697+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.5/10EPSS 0.53%

Last modified Jun 17, 2026

CVE-2024-21500 is a medium-severity vulnerability rated 6.5/10 on the CVSS scale. All versions of the package github.com/greenpau/caddy-security are vulnerable to Improper Restriction of Excessive Authentication Attempts via the two-factor authentication (2FA). Although the application blocks the user after several failed attempts to provide 2FA codes, attackers can bypass this blocking mechanism by automating the application’s full multistep 2FA process.. EPSS estimates a 0.53% chance of exploitation in the next 30 days.

Description

All versions of the package github.com/greenpau/caddy-security are vulnerable to Improper Restriction of Excessive Authentication Attempts via the two-factor authentication (2FA). Although the application blocks the user after several failed attempts to provide 2FA codes, attackers can bypass this blocking mechanism by automating the application’s full multistep 2FA process.

Metrics

CVSS 3.1

6.5/10

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

EPSS Probability

0.53%

41.0th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Authcrunch	Caddy-Security	All versions

References

https://blog.trailofbits.com/2023/09/18/security-flaws-in-an-sso-plugin-for-caddy/Exploit, Third Party Advisory
https://github.com/greenpau/caddy-security/issues/271Issue Tracking
https://security.snyk.io/vuln/SNYK-GOLANG-GITHUBCOMGREENPAUCADDYSECURITY-6249864Third Party Advisory
https://blog.trailofbits.com/2023/09/18/security-flaws-in-an-sso-plugin-for-caddy/Exploit, Third Party Advisory
https://github.com/greenpau/caddy-security/issues/271Issue Tracking
https://security.snyk.io/vuln/SNYK-GOLANG-GITHUBCOMGREENPAUCADDYSECURITY-6249864Third Party Advisory

Timeline

Published: Feb 17, 2024
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2024-21500?

How severe is CVE-2024-21500?

CVE-2024-21500 has a CVSS score of 6.5/10 (MEDIUM severity). The EPSS model estimates a 0.53% probability of exploitation in the next 30 days.

How do I fix CVE-2024-21500?

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-2024-21500?

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

Scan your code now

Source: NVD / NIST