Cyber Resilience

CVE-2026-42884

Access Control

Published
11 May 2026
Modified
17 June 2026
CVSS Score v3.1 4.3
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
EPSS Score 0.0016 6th percentile
Risk Priority 35 floored blend · peak EPSS

Summary

CVE-2026-42884 is a medium-severity Incorrect Authorization (CWE-863) vulnerability. Its CVSS base score is 4.3 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Data from Information Repositories (T1213); ranked at the 6th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to AC-3 (Access Enforcement) and AC-4 (Information Flow Enforcement) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Audiobookshelf is a self-hosted audiobook and podcast server. Prior to 2.32.2, the GET /api/collections and GET /api/collections/:id endpoints return collections from all libraries without checking whether the requesting user has access to each collection's library. An authenticated user with access…

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to any library can enumerate and read collections (including full book metadata) from libraries they are explicitly restricted from accessing. This vulnerability is fixed in 2.32.2.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1213 Data from Information Repositories Collection
Adversaries may leverage information repositories to mine valuable information.
Why these techniques?

Broken access control on collection/book metadata endpoints enables unauthorized data retrieval from information repositories.

Confidence: MEDIUM · MITRE ATT&CK Enterprise v19.0

CVEs Like This One

CVE-2025-62394Shared CWE-863
CVE-2025-30155Shared CWE-863
CVE-2026-35596Shared CWE-863
CVE-2025-53902Shared CWE-863
CVE-2025-54877Shared CWE-863
CVE-2026-49092Shared CWE-863
CVE-2026-33676Shared CWE-863
CVE-2026-27153Shared CWE-863
CVE-2026-33460Shared CWE-863
CVE-2024-13278Shared CWE-863

Affected Assets

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
  • AC-3 Access Enforcement
  • AC-4 Information Flow Enforcement
  • AC-6 Least Privilege
Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 5 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly enforces per-library authorization checks on the /api/collections endpoints so users cannot retrieve collections or book metadata from libraries they are restricted from accessing.

prevent

Enforces information-flow rules that prevent collection and metadata data from crossing library access boundaries for authenticated users.

prevent

Limits each user to the minimum set of libraries, reducing the scope of collections that could be enumerated if the endpoint authorization check is missing.

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 mostly match
prevents

Defining, enforcing, and reviewing access authorizations and least privilege directly prevents incorrect authorization checks.

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.

prevents

Requiring consistency between access rights and classification plus formal approval steps ensures that the authorization logic correctly distinguishes between entities that should and should not be granted access.

prevents

Enforcing policy-driven approval and role-change reviews stops incorrect or stale authorization decisions from remaining in effect after job changes or terminations.

prevents

By tying access rights to identity, device, location and classification, the control reduces the likelihood that an authorization decision will be based on an incorrect or bypassed policy.

References