Cyber Resilience

CVE-2023-25160

Access Control in Nextcloud Mail ≤ 1.11.8

Published
13 February 2023
Modified
21 November 2024
Patch / advisory
CVSS Score v3.1 4.1
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:N/A:N
EPSS Score 0.0046 38th percentile
Risk Priority 34 floored blend · peak EPSS

Summary

CVE-2023-25160 is a medium-severity Authorization Bypass Through User-Controlled Key (CWE-639) vulnerability in Nextcloud Mail. Its CVSS base score is 4.1 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 38th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Nextcloud Mail is an email app for the Nextcloud home server platform. Prior to versions 2.2.1, 1.14.5, 1.12.9, and 1.11.8, an attacker can access the mail box by ID getting the subjects and the first characters of the emails. Users…

more

should upgrade to Mail 2.2.1 for Nextcloud 25, Mail 1.14.5 for Nextcloud 22-24, Mail 1.12.9 for Nextcloud 21, or Mail 1.11.8 for Nextcloud 20 to receive a patch. No known workarounds are available.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-33184Same product: Nextcloud Mail
CVE-2023-48307Same product: Nextcloud Mail
CVE-2023-23943Same product: Nextcloud Mail
CVE-2023-45660Same product: Nextcloud Mail
CVE-2025-66514Same product: Nextcloud Mail
CVE-2024-52509Same product: Nextcloud Mail
CVE-2025-66551Same vendor: Nextcloud
CVE-2025-66553Same vendor: Nextcloud
CVE-2025-64011Same vendor: Nextcloud
CVE-2026-45810Same vendor: Nextcloud

Affected Assets

nextcloud
mail
≤ 1.11.8 · 1.12.0 — 1.12.9 · 1.13.0 — 1.14.5

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-639

Per-request decision making makes it harder to bypass authorization using user-controlled keys without proper validation in the decision process.

addresses: CWE-639

Consistent enforcement of approved authorizations makes bypassing via user-controlled keys ineffective.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.AA-05 full match
prevents

Enforcing authorization policy and least privilege directly blocks user-controlled key tampering that bypasses access checks.

PR.IR-01 mostly match
prevents

Logical access controls prevent unauthorized data access that results from missing authorization checks on object references.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Security testing can detect missing authorization checks but does not prevent the weakness in production.

prevents

Information access restriction explicitly enforces that users may only retrieve data they are authorized to see, directly addressing user-controlled key bypass.

prevents

Access control policy directly requires enforcement of authorization rules that prevent unauthorized access via manipulated keys.

prevents

Managing access rights includes ensuring users can only access their own records and not bypass authorization by altering identifiers.

mitigates

Privileged access rights control restricts what data each user may access, mitigating direct object reference attacks.

prevents

Secure development lifecycle includes authorization design but does not itself implement runtime access checks.

References