Security readout for executives and security teams
Plain-English summary
An authenticated Nextcloud user could view email metadata belonging to other users through vulnerable Nextcloud Mail versions. This is a privacy and business-confidentiality issue because email metadata can expose relationships and activity. The vendor identifies fixed versions and says no workaround is known beyond patching.
Executive priority
Prioritize remediation for shared Nextcloud environments because any authenticated user boundary weakness in mail metadata can affect privacy, confidentiality, and trust. Patch promptly, especially where external users, contractors, or broad internal populations have accounts.
Technical view
CVE-2021-32652 is a CWE-284 missing permission check in Nextcloud Mail. Sources list affected ranges as versions below 1.4.3 and versions from 1.5.5 through below 1.8.2. The flaw is network-reachable, low-complexity, requires login, and needs no user interaction.
Likely exposure
Exposure is likely limited to organizations running Nextcloud with the Mail app in the affected version ranges and multiple authenticated users. Systems without Nextcloud Mail, or already updated to 1.4.3 or 1.8.2 or later, are not indicated as affected by the supplied sources.
Exploitation context
The bundle does not show CISA KEV listing or other cited evidence of active exploitation. The attacker must already be authenticated, but the CVSS score is high because the permission failure can expose other users' mail metadata.
Researcher notes
Evidence is concise: the public advisory describes missing authorization before metadata retrieval and names fixed versions. The source bundle does not include proof-of-concept details, observed exploitation, or alternative mitigations, so validation should focus on version exposure and vendor guidance.
Mitigation direction
- Upgrade Nextcloud Mail to 1.4.3, 1.8.2, or a later fixed release.
- Treat patching as required; sources state no workaround is known.
- Inventory Nextcloud instances and confirm the installed Mail app version.
- Review vendor advisory updates before making operational exceptions.
Validation and detection
- Confirm whether Nextcloud Mail is installed on each Nextcloud instance.
- Record the Mail app version and compare it with affected ranges.
- Verify updated systems report version 1.4.3, 1.8.2, or later.
- Review access logs for unusual authenticated metadata access where available.
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-284: Authorization and privilege behavior lookup
Authorization weaknesses can support privilege escalation and valid-account review, depending on exploit path. 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-2021-32652 mapping review
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Open ATT&CK lookup- Severity
- High
- CVSS
- 8.8 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
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:H/I:H/A:H2.85.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
8.8HighVector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/nextcloud/security-advisories/security/advisories/GHSA-mxx2-6rg9-v2vcCVE reference · x_refsource_CONFIRM
- https://hackerone.com/reports/1094063CVE reference · x_refsource_MISC
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.
Improper Access Control
Improper Access Control represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.