Security readout for executives and security teams
Plain-English summary
The Nextcloud command-line sync tool could accept bad TLS certificates before version 3.6.1. If an organization used nextcloudcmd in scripts or on headless systems, a network attacker positioned between client and server could potentially intercept sensitive data or credentials. The regular GUI desktop clients and Nextcloud server are not affected.
Executive priority
Treat this as targeted hygiene, not an emergency. Patch affected CLI installations, especially automation handling credentials or sensitive files, but do not assume broad Nextcloud server compromise from this CVE alone.
Technical view
CVE-2022-39334 is a CWE-295 certificate validation flaw in nextcloudcmd versions before 3.6.1. The CLI incorrectly trusted invalid TLS certificates, weakening transport authenticity and enabling man-in-the-middle exposure under the right network conditions. CVSS is 3.9, with low confidentiality and integrity impact and no availability impact.
Likely exposure
Exposure is limited to environments running nextcloudcmd before 3.6.1, especially automation, scripts, and headless servers. Standard Nextcloud GUI desktop clients and Nextcloud server deployments are outside the stated affected scope.
Exploitation context
The source bundle does not show KEV listing or confirmed active exploitation. Practical abuse would require a suitable man-in-the-middle position and a victim workflow using the vulnerable CLI against an invalid certificate path.
Researcher notes
Evidence supports a narrow CLI-only TLS validation issue. Do not generalize impact to the GUI desktop client or server. The provided CVSS vector is low severity, but operational risk rises where nextcloudcmd runs unattended with sensitive credentials.
Mitigation direction
- Upgrade nextcloudcmd to version 3.6.1 or later.
- Apply vendor or distribution security updates where nextcloudcmd is packaged.
- Prioritize automated or headless systems that run nextcloudcmd unattended.
- Check Nextcloud and distribution advisories for environment-specific guidance.
Validation and detection
- Inventory systems and scripts that call nextcloudcmd.
- Verify installed nextcloudcmd versions are 3.6.1 or later.
- Confirm exposure review excludes GUI desktop clients and servers unless they also run nextcloudcmd.
- Review automation paths that connect across untrusted or shared networks.
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-295: 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-2022-39334 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
- Low
- CVSS
- 3.9 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N
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:L/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N1.32.5Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
3.9LowVector: CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/nextcloud/security-advisories/security/advisories/GHSA-82xx-98xv-4jxvCVE reference
- https://github.com/nextcloud/desktop/issues/4927CVE reference
- https://github.com/nextcloud/desktop/pull/5022CVE reference
- https://hackerone.com/reports/1699740CVE reference
- https://lists.debian.org/debian-lts-announce/2025/09/msg00018.htmlCVE reference
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 Certificate Validation
Improper Certificate Validation represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.