How severe is CVE-2021-32678?

CVE-2021-32678 has a CVSS 3.x base score of 3.7, rated low severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2021-32678 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-32678?

CVE-2021-32678 primarily affects Nextcloud Nextcloud Server. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-32678?

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

When was CVE-2021-32678 published?

CVE-2021-32678 was published on 2021-07-12 and last updated on 2026-06-17.

CVE-2021-32678

CVE-2021-32678 is a low-severity vulnerability in Nextcloud Nextcloud Server with a CVSS 3.x base score of 3.7. 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-307.

Key facts

Severity: Low (CVSS 3.x base score 3.7)
CVSS v2: 5.0
EPSS exploit prediction: 1% (69th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-307
Affected product: Nextcloud Nextcloud Server
Published: 2021-07-12
Last modified: 2026-06-17

Description

Nextcloud Server is a Nextcloud package that handles data storage. In versions prior to 19.0.13, 20.0.11, and 21.0.3, ratelimits are not applied to OCS API responses. This affects any OCS API controller (`OCSController`) using the `@BruteForceProtection` annotation. Risk depends on the installed applications on the Nextcloud Server, but could range from bypassing authentication ratelimits or spamming other Nextcloud users. The vulnerability is patched in versions 19.0.13, 20.0.11, and 21.0.3. No workarounds aside from upgrading are known to exist.

Frequently asked questions

What is CVE-2021-32678?: Nextcloud Server is a Nextcloud package that handles data storage. In versions prior to 19.0.13, 20.0.11, and 21.0.3, ratelimits are not applied to OCS API responses. This affects any OCS API controller (`OCSController`) using the `@BruteForceProtection` annotation. Risk depends on the installed applications on the Nextcloud Server, but could range from bypassing authentication ratelimits or spamming other Nextcloud users. The vulnerability is patched in versions 19.0.13, 20.0.11, and 21.0.3. No workarounds aside from upgrading are known to exist.
How severe is CVE-2021-32678?: CVE-2021-32678 has a CVSS 3.x base score of 3.7, rated low severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2021-32678 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-32678?: CVE-2021-32678 primarily affects Nextcloud Nextcloud Server. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-32678?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-32678 published?: CVE-2021-32678 was published on 2021-07-12 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*

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