CVE-2023-39953 - CVE House
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Status published Medium CVE-2023-39953

Issuer not verified from obtained token in user_oidc

Vulnerability Description

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.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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Affected Vendor

Affected Software

security-advisories
Vulnerable Versions:
>= 1.0.0, < 1.3.3

Timeline

Official Publish: August 10th, 2023
Last Modified: October 3rd, 2024
Added to House: July 22nd, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N

Weaknesses (CWE)

CWE-303

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.