How severe is CVE-2021-29452?

CVE-2021-29452 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2021-29452 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (52nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-29452?

CVE-2021-29452 affects Curveballjs A12n-server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-29452?

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-2021-29452 published?

CVE-2021-29452 was published on 2021-04-16 and last updated on 2026-06-17.

CVE-2021-29452

CVE-2021-29452 is a high-severity vulnerability in Curveballjs A12n-server with a CVSS 3.x base score of 8.1. 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-863.

Key facts

Severity: High (CVSS 3.x base score 8.1)
CVSS v2: 4.0
EPSS exploit prediction: 1% (52nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-863
Affected product: Curveballjs A12n-server
Published: 2021-04-16
Last modified: 2026-06-17

Description

a12n-server is an npm package which aims to provide a simple authentication system. A new HAL-Form was added to allow editing users in version 0.18.0. This feature should only have been accessible to admins. Unfortunately, privileges were incorrectly checked allowing any logged in user to make this change. Patched in v0.18.2.

Frequently asked questions

What is CVE-2021-29452?: a12n-server is an npm package which aims to provide a simple authentication system. A new HAL-Form was added to allow editing users in version 0.18.0. This feature should only have been accessible to admins. Unfortunately, privileges were incorrectly checked allowing any logged in user to make this change. Patched in v0.18.2.
How severe is CVE-2021-29452?: CVE-2021-29452 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2021-29452 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (52nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-29452?: CVE-2021-29452 affects Curveballjs A12n-server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-29452?: 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-2021-29452 published?: CVE-2021-29452 was published on 2021-04-16 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:curveballjs:a12n-server:*:*:*:*:*:node.js:*:*

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