Cyber Resilience

CVE-2026-54563

Access Control

Published
15 July 2026
Modified
15 July 2026
CVSS Score v3.1 7.1
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N
EPSS Score 0.0019 8th percentile
Risk Priority 55 floored blend · peak EPSS

Summary

CVE-2026-54563 is a high-severity Incorrect Authorization (CWE-863) vulnerability. Its CVSS base score is 7.1 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Data from Local System (T1005); ranked at the 8th 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 SI-10 (Information Input Validation) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Cloudreve is a self-hosted file management and sharing system. Prior to 4.16.1, a Cloudreve WebDAV account rooted at a configured folder can send paths such as /dav/%2e%2e/outside.txt because stripPrefix in pkg/webdav/webdav.go joins the decoded request suffix to the account root…

more

with fs.URI.JoinRaw without checking containment, allowing the scoped credential to read and list files outside the configured folder and writable credentials to create, overwrite, move, or delete them. This issue is reported as fixed in version 4.16.1.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1005 Data from Local System Collection
Adversaries may search local system sources, such as file systems, configuration files, local databases, virtual machine files, or process memory, to find files of interest and sensitive data prior to Exfiltration.
T1083 File and Directory Discovery Discovery
Adversaries may enumerate files and directories or may search in specific locations of a host or network share for certain information within a file system.
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.
Why these techniques?

Path traversal in WebDAV allows scoped credentials to read/list/create/delete files outside root (T1005, T1083); exploits public-facing WebDAV app (T1190).

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

CVEs Like This One

CVE-2026-40515Shared CWE-863
CVE-2026-6863Shared CWE-863
CVE-2026-3526Shared CWE-863
CVE-2026-28715Shared CWE-863
CVE-2026-42438Shared CWE-863
CVE-2026-41908Shared CWE-863
CVE-2026-26336Shared CWE-863
CVE-2026-24748Shared CWE-863
CVE-2026-63733Shared CWE-863
CVE-2025-30743Shared CWE-863

Affected Assets

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
  • AC-3 Access Enforcement
  • SI-10 Information Input Validation
  • AC-4 Information Flow Enforcement
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 that WebDAV requests from a scoped account remain confined to its configured root folder, blocking the path traversal that bypasses containment checks.

prevent

Requires validation of incoming WebDAV paths (including percent-decoded segments) to reject traversal sequences such as %2e%2e before they reach fs.URI.JoinRaw.

prevent

Enforces information-flow rules that prevent data movement between the account root and any parent or sibling directories outside the intended scope.

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