Vulnerability · CVE-2020-8133
Message Authentication Codes calculated by the Default Encryption Module allow an attacker to silently overwrite blocks in a file
Published Aug 26, 2020 · Nextcloud Nextcloud
Open the advisory
Exploitation likelihood is not on this record for CVE-2020-8133. A missing EPSS score is not a low risk. Compare Nextcloud Nextcloud with the linked advisory before you change production.
Gaps on this record
- No version range is stored. A customer cannot check an installed version against this record.
- No vendor fix or required action is stored. Compare the linked advisory before you change production.
- EPSS is missing. A missing score is not a low risk.
- Severity
- Unknown—
- Known exploitation
- Not in CISA/VulnCheck KEV
- EPSS
- Not in the current FIRST EPSS dataset
- Remediation
- Not established
- Affected products
- Nextcloud Nextcloud
Message Authentication Codes calculated by the Default Encryption Module allow an attacker to silently overwrite blocks in a file
No affected version ranges are stored yet. Use the vendor advisory before you decide this record does not apply.
How to fix CVE-2020-8133
Recommended remediation
No required-action text, fix commit, or clear fixed-version range is stored yet.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
Exploitation likelihood is not on this record for CVE-2020-8133. A missing EPSS score is not a low risk. Compare Nextcloud Nextcloud with the linked advisory before you change production.
Which versions are affected?
Affected version ranges are not on this record. Compare the installed version with the linked vendor advisory before you change production.
What should an analyst verify?
No weakness class is stored. EPSS is absent from the current FIRST dataset. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Code
The project this record applies to. Exploit listings stay in References.
No public source repository is identified for this product.
Timeline
Detection, updates, and resolution for this record.
Aug 26, 2020 · Nextcloud Security
Detected
Message Authentication Codes calculated by the Default Encryption Module allow an attacker to silently overwrite blocks in a file
Sources
- CVE.orgVulnerability recordCVE-2020-8133
Official CVE identifier
cve.org - Nextcloud SecurityVendor advisoryCVE-2020-8133
Message Authentication Codes calculated by the Default Encryption Module allow an attacker to silently overwrite blocks in a file
github.com
Freshness
Last verified in this catalog Oct 23, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.