XSS in Nextcloud Openid Connect User Backend
CVE-2022-39338
user_oidc is an OpenID Connect user backend for Nextcloud. Versions prior to 1.2.1 did not properly validate discovery urls which may lead to a stored cross site scripting attack vector. The impact is limited due to the restrictive CSP that is applied on this endpoint. Additionally this vulnerability has only been shown to be exploitable in the Safari web browser. This issue has been addressed in version 1.2.1. Users are advised to upgrade. Users unable to upgrade should urge their users to avoid using the Safari web browser.
Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 3.5 (Low). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:L/I:L/A:N.
EPSS exploit prediction
EPSS: 0.006 (48.2th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 48th percentile — 48.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: +0.000
Affected products
- Nextcloud Openid Connect User Backend
- Nextcloud Security-Advisories — versions < 1.2.1
Weakness classification (CWE)
References
- github.com/nextcloud/security-advisories/security/advisories/GHSA-5fpw-795h-rg57 (Third Party Advisory)
- github.com/nextcloud/user_oidc/pull/496 (Patch, Third Party Advisory)
- hackerone.com/reports/1687410 (Permissions Required, Third Party Advisory)
Frequently asked questions
- What is CVE-2022-39338?
- CVE-2022-39338 is a low-severity vulnerability in Nextcloud Openid Connect User Backend, classified under Improper Input Validation. CVSS score: 3.5/10. Published 2022-11-25.
- How severe is CVE-2022-39338?
- Low severity. CVSS v3 base score is 3.5 out of 10.