How severe is CVE-2021-22879?

CVE-2021-22879 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-22879 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (91st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-22879?

CVE-2021-22879 primarily affects Nextcloud Desktop. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-22879?

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-2021-22879 published?

CVE-2021-22879 was published on 2021-04-14 and last updated on 2026-06-17.

CVE-2021-22879

CVE-2021-22879 is a high-severity vulnerability in Nextcloud Desktop with a CVSS 3.x base score of 8.8. 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-74.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 6.8
EPSS exploit prediction: 5% (91st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-74
Affected product: Nextcloud Desktop
Published: 2021-04-14
Last modified: 2026-06-17

Description

Nextcloud Desktop Client prior to 3.1.3 is vulnerable to resource injection by way of missing validation of URLs, allowing a malicious server to execute remote commands. User interaction is needed for exploitation.

Frequently asked questions

What is CVE-2021-22879?: Nextcloud Desktop Client prior to 3.1.3 is vulnerable to resource injection by way of missing validation of URLs, allowing a malicious server to execute remote commands. User interaction is needed for exploitation.
How severe is CVE-2021-22879?: CVE-2021-22879 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-22879 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (91st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-22879?: CVE-2021-22879 primarily affects Nextcloud Desktop. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-22879?: 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-2021-22879 published?: CVE-2021-22879 was published on 2021-04-14 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:nextcloud:desktop:*:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*

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