Cyber Resilience

CVE-2023-39953

Medium

Published: 10 August 2023

Published
10 August 2023
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 4.8 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N
EPSS Score 0.0061 70.3th percentile
Risk Priority 10 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2023-39953 is a medium-severity Incorrect Implementation of Authentication Algorithm (CWE-303) vulnerability in Nextcloud User Oidc. Its CVSS base score is 4.8 (Medium).

Operationally, ranked in the top 29.7% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

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…

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known token they also have access to. user_oidc 1.3.3 contains a patch. No known workarounds are available.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

nextcloud
user oidc
1.0.0 — 1.3.3

Mitigating Controls

No mitigating controls mapped yet. The per-CVE control annotator has not reached this CVE.

References