user_oidc is an OpenID Connect user backend for Nextcloud. In versions prior to 1.2.1 sensitive information such as the OIDC client credentials and tokens are sent in plain text of HTTP without TLS. Any malicious actor with access to monitor user traffic may have been able to compromise account security. This issue has been addressed in in user_oidc v1.2.1. Users are advised to upgrade. Users unable to upgrade may use https to access Nextcloud. Set an HTTPS discovery URL in the provider settings (in Nextcloud OIDC admin settings).
Conclusion & alert: CVE-2022-39339 is rated Low Risk (29/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.42%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-06-15 | 0.24% | 0.42% | +0.18% |
| 2 | 2026-06-11 | 0.30% | 0.24% | -0.07% |
| 3 | 2026-05-21 | — | 0.30% | — |
Full EPSS history (35 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 4.3 | 3.1 | MEDIUM |
|
2.8 | 1.4 | [email protected] |
| 4.3 | 3.1 | MEDIUM |
|
2.8 | 1.4 | [email protected] |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| nextcloud | openid_connect_user_backend | < 1.2.1 | cpe:2.3:a:nextcloud:openid_connect_user_backend:*:*:*:*:*:nextcloud:*:* |
| URL | Tags |
|---|---|
| https://github.com/nextcloud/security-advisories/security/advisories/GHSA-2vff-cq8h-chhg | Patch Third Party Advisory |
| https://github.com/nextcloud/user_oidc/pull/495 | Patch Third Party Advisory |
| https://hackerone.com/reports/1687005 | Permissions Required Third Party Advisory |