CVSS 3.1
4.8 mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:NCVE-2023-39953
Medium (4.8) in nextcloud user oidc. EPSS 0.5% chance of exploitation in the next 30 days.
user_oidc provides the OIDC connect user backend for Nextcloud, an open-source cloud platform. Starting in version 1.0.0 and prior to version 1.3.3, missing verification of the issuer would have allowed an attacker to perform a man-in-the-middle attack returning corrupted or known token they also have access to. user_oidc 1.3.3 contains a patch. No known workarounds are available.
Severity
- EPSS
- 0.5% chance of exploitation in the next 30 days; higher than 45% of CVEs (scores of 2026-10-31)
- CWE
- CWE-303
- Published
- Modified
- Record from
- the NVD, synced
Affected
- nextcloud:user_oidc
References
- https://github.com/nextcloud/security-advisories/security/advisories/GHSA-xx3h-v363-q36j
- https://github.com/nextcloud/user_oidc/pull/642
- https://hackerone.com/reports/2021684
- https://github.com/nextcloud/security-advisories/security/advisories/GHSA-xx3h-v363-q36j
- https://github.com/nextcloud/user_oidc/pull/642