How severe is CVE-2021-21329?

CVE-2021-21329 has a CVSS 3.x base score of 8.7, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2021-21329 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-21329?

CVE-2021-21329 affects Ratcf. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-21329?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-21329 published?

CVE-2021-21329 was published on 2021-03-08 and last updated on 2026-06-17.

CVE-2021-21329

CVE-2021-21329 is a high-severity vulnerability in Ratcf with a CVSS 3.x base score of 8.7. 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-287.

Key facts

Severity: High (CVSS 3.x base score 8.7)
CVSS v2: 6.8
EPSS exploit prediction: 1% (70th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Ratcf
Published: 2021-03-08
Last modified: 2026-06-17

Description

RATCF is an open-source framework for hosting Cyber-Security Capture the Flag events. In affected versions of RATCF users with multi factor authentication enabled are able to log in without a valid token. This is fixed in commit cebb67b.

Frequently asked questions

What is CVE-2021-21329?: RATCF is an open-source framework for hosting Cyber-Security Capture the Flag events. In affected versions of RATCF users with multi factor authentication enabled are able to log in without a valid token. This is fixed in commit cebb67b.
How severe is CVE-2021-21329?: CVE-2021-21329 has a CVSS 3.x base score of 8.7, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2021-21329 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-21329?: CVE-2021-21329 affects Ratcf. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-21329?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-21329 published?: CVE-2021-21329 was published on 2021-03-08 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:ratcf:ratcf:*:*:*:*:*:*:*:*

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