How severe is CVE-2024-21500?

CVE-2024-21500 has a CVSS 3.x base score of 4.8, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2024-21500 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2024-21500?

CVE-2024-21500 affects Authcrunch Caddy-security. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2024-21500?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2024-21500 have an EU (EUVD) identifier?

Yes. CVE-2024-21500 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-0731.

When was CVE-2024-21500 published?

CVE-2024-21500 was published on 2024-02-17 and last updated on 2026-06-17.

CVE-2024-21500

CVE-2024-21500 is a medium-severity vulnerability in Authcrunch Caddy-security with a CVSS 3.x base score of 4.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-307.

Key facts

Severity: Medium (CVSS 3.x base score 4.8)
EPSS exploit prediction: 1% (41st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-0731
Weakness: CWE-307
Affected product: Authcrunch Caddy-security
Published: 2024-02-17
Last modified: 2026-06-17

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.

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.
How severe is CVE-2024-21500?: CVE-2024-21500 has a CVSS 3.x base score of 4.8, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2024-21500 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-21500?: CVE-2024-21500 affects Authcrunch Caddy-security. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2024-21500?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2024-21500 have an EU (EUVD) identifier?: Yes. CVE-2024-21500 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-0731.
When was CVE-2024-21500 published?: CVE-2024-21500 was published on 2024-02-17 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:authcrunch:caddy-security:*:*:*:*:*:*:*:*

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