How severe is CVE-2020-8133?

CVE-2020-8133 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2020-8133 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-8133?

CVE-2020-8133 affects Nextcloud Nextcloud Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-8133?

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

When was CVE-2020-8133 published?

CVE-2020-8133 was published on 2020-11-09 and last updated on 2026-06-17.

CVE-2020-8133

CVE-2020-8133 is a medium-severity vulnerability in Nextcloud Nextcloud Server with a CVSS 3.x base score of 5.3. 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-347.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 5.0
EPSS exploit prediction: 1% (51st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-347
Affected product: Nextcloud Nextcloud Server
Published: 2020-11-09
Last modified: 2026-06-17

Description

A wrong generation of the passphrase for the encrypted block in Nextcloud Server 19.0.1 allowed an attacker to overwrite blocks in a file.

Frequently asked questions

What is CVE-2020-8133?: A wrong generation of the passphrase for the encrypted block in Nextcloud Server 19.0.1 allowed an attacker to overwrite blocks in a file.
How severe is CVE-2020-8133?: CVE-2020-8133 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2020-8133 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-8133?: CVE-2020-8133 affects Nextcloud Nextcloud Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-8133?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-8133 published?: CVE-2020-8133 was published on 2020-11-09 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:nextcloud:nextcloud_server:19.0.1:*:*:*:*:*:*:*

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