Security readout for executives and security teams
Plain-English summary
An authenticated Nextcloud user could make the user administration page unusable, preventing admins from managing users through the web interface. The disclosed impact is limited availability loss for administration, not data theft or code execution. The issue is fixed in Nextcloud Server 19.0.11, 20.0.10, and 21.0.2.
Executive priority
Treat this as a moderate operational resilience issue. It can block user administration but is not described as data theft, privilege escalation, or remote code execution. Patch during the next maintenance window unless user administration availability is business-critical.
Technical view
CVE-2021-32657 affects Nextcloud Server <19.0.11, 20.0.0-20.0.9, and 21.0.0-21.0.1. It is rated CVSS 4.3 with network access, low complexity, and low privileges required. Sources classify it as CWE-400, causing low availability impact to the user administration page.
Likely exposure
Exposure is likely limited to organizations running affected Nextcloud Server versions with untrusted or broad user populations. The issue requires a malicious authenticated user, so public internet exposure matters less than who can log in.
Exploitation context
The provided sources do not report active exploitation, and the CVE is not listed as KEV. Public detail indicates an authenticated user can disrupt the admin user-management page, but the bundle does not provide evidence of broader compromise.
Researcher notes
The source bundle is consistent on affected release ranges and fixed versions, except one description line appears to say 10.0.11 while affected data and fix text indicate 19.0.11. No exploit status beyond advisory disclosure is provided.
Mitigation direction
- Upgrade Nextcloud Server to 19.0.11, 20.0.10, 21.0.2, or later.
- Use the OCC command-line tool for user administration until patched.
- Check the Nextcloud advisory for version-specific guidance.
- Review Gentoo GLSA guidance if using Gentoo-packaged Nextcloud.
Validation and detection
- Inventory Nextcloud Server instances and record exact versions.
- Flag versions <19.0.11, 20.0.0-20.0.9, or 21.0.0-21.0.1.
- Confirm the web user administration page remains usable after patching.
- Verify administrators can use OCC as a temporary workaround.
- Review access policies for untrusted authenticated users.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-400: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2021-32657 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 4.3 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L2.81.4Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
4.3MediumVector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/nextcloud/security-advisories/security/advisories/GHSA-fx62-q47f-f665CVE reference · x_refsource_CONFIRM
- https://hackerone.com/reports/1147611CVE reference · x_refsource_MISC
- GLSA-202208-17CVE reference · vendor-advisory, x_refsource_GENTOO
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Uncontrolled Resource Consumption
Uncontrolled Resource Consumption represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.