CVE-2024-21500: caddy-security Brute Force — Exploit

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.

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CVSS v3.1 Score

4.8

MEDIUM

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

Weakness Type (CWE)

CWE-307 CWE-307

Affected Products

Vendor	Product	Versions
authcrunch	caddy-security	All

References

Exploits

https://blog.trailofbits.com/2023/09/18/security-flaws-in-an-sso-plugin-for-caddy/ https://blog.trailofbits.com/2023/09/18/security-flaws-in-an-sso-plugin-for-caddy/

Other References

https://github.com/greenpau/caddy-security/issues/271 https://security.snyk.io/vuln/SNYK-GOLANG-GITHUBCOMGREENPAUCADDYSECURITY-6249864 https://github.com/greenpau/caddy-security/issues/271 https://security.snyk.io/vuln/SNYK-GOLANG-GITHUBCOMGREENPAUCADDYSECURITY-6249864

Frequently Asked Questions

What is CVE-2024-21500? +

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. It has a CVSS v3.1 base score of 4.8 (MEDIUM).

How severe is CVE-2024-21500? +

CVE-2024-21500 has a CVSS v3.1 score of 4.8 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-2024-21500? +

CVE-2024-21500 affects products from authcrunch, specifically: caddy-security. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2024-21500? +

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-2024-21500