Cyber Resilience

CVE-2026-54066

Path Traversal

Published
24 June 2026
Modified
25 June 2026
CVSS Score v3.1 7.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
EPSS Score 0.019 78th percentile
Risk Priority 61 floored blend · peak EPSS

Summary

CVE-2026-54066 is a high-severity Path Traversal (CWE-22) vulnerability. Its CVSS base score is 7.5 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Default Accounts (T1078.001); ranked in the top 22% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to AC-3 (Access Enforcement) and CM-2 (Baseline Configuration) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

SiYuan is an open-source personal knowledge management system. Prior to 3.7.0, the patch for CVE-2026-41894 ("Path Traversal via Double URL Encoding") sanitized the /export/ route but the identical root cause remains in the /assets/*path route. In publish mode (anonymous read-only…

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HTTP endpoint, default port 6808), an unauthenticated remote attacker can read arbitrary files inside WorkspaceDir — including conf/conf.json (which contains the AccessAuthCode SHA256 hash, API token, and sync keys), temp/siyuan.db, temp/blocktree.db, and siyuan.log — by double-URL-encoding .. segments. This vulnerability is fixed in 3.7.0.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1078.001 Default Accounts Stealth
Adversaries may obtain and abuse credentials of a default account as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion.
T1078 Valid Accounts Stealth
Adversaries may obtain and abuse credentials of existing accounts as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion.
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.
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.
T1133 External Remote Services Persistence
Adversaries may leverage external-facing remote services to initially access and/or persist within a network.
T1542.002 Component Firmware Stealth
Adversaries may modify component firmware to persist on systems.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-25499Shared CWE-1188, CWE-22
CVE-2025-1863Shared CWE-1188
CVE-2024-41995Shared CWE-1188
CVE-2026-62185Shared CWE-1188
CVE-2025-7353Shared CWE-1188
CVE-2024-30124Shared CWE-1188
CVE-2025-56332Shared CWE-1188
CVE-2024-22388Shared CWE-1188
CVE-2018-25193Shared CWE-1188
CVE-2026-33376Shared CWE-1188

Affected Assets

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 13 hardening rules · 7 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V14.3.2
  • V6.3.2
  • V11.3.1
  • V13.2.3

Mitigating Controls (NIST 800-53 r5) AI

Enforces the intended directory access authorizations that path traversal would otherwise bypass.

Baseline configuration directly requires documenting and maintaining secure initial settings instead of insecure defaults.

Configuration settings mandate the most restrictive values be applied at initialization, eliminating reliance on insecure factory defaults.

Input validation directly neutralizes special path elements before pathname construction occurs.

Information-flow rules can be configured to reject traversals that would move data outside an approved directory boundary.

Least privilege reduces the impact of any unauthorized file access obtained via traversal.

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.PS-01 full match
prevents

Hardened baselines and configuration management directly replace insecure defaults with secure settings.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly require input validation and path sanitization that prevent relative traversal.

ID.RA-09 partial match
prevents

Pre-acquisition integrity checks can reject products known to ship with insecure defaults.

PR.PS-02 partial match
prevents

Patching/maintenance can remediate known path-traversal flaws in deployed software (partial prevention of exploitability) but does nothing to stop the coding defect from being introduced in the first place.

PR.AA-05 none match
prevents

PR.AA-05 defines and reviews access policies but does not address code-level pathname neutralization, so neither direction prevents CWE-22.

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 in development catches path traversal via static/dynamic analysis.

prevents

Mandating secure baseline templates and immediate replacement of vendor defaults directly stops systems from being deployed with insecure factory settings that attackers can exploit.

prevents

Secure SDLC mandates input validation and path sanitization that directly prevent path traversal.

prevents

Application security requirements include rules for safe file handling and canonicalization.

prevents

Secure architecture principles require least-privilege file access and directory isolation.

prevents

Secure coding standards explicitly forbid unsafe path construction and mandate safe APIs.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).

Oracle Linux 8 (1 rule)
  • V-248823 OL 8 must not have the telnet-server package installed. prevents CWE-1188
RHEL 7 (1 rule)
  • V-204627 SNMP community strings on the Red Hat Enterprise Linux operating system must be changed from the default. prevents CWE-1188
Ubuntu 22.04 (1 rule)
  • V-260529 Ubuntu 22.04 LTS must be configured so that remote X connections are disabled, unless to fulfill documented and validated mission requirements. prevents CWE-1188
Ubuntu 24.04 (1 rule)
  • V-270708 Ubuntu 24.04 LTS must be configured so that remote X connections are disabled, unless to fulfill documented and validated mission requirements. prevents CWE-1188
Windows Server 2016 (1 rule)
  • V-224972 Active Directory Group Policy objects must have proper access control permissions. prevents CWE-1188
Windows Server 2019 (1 rule)
  • V-205741 Windows Server 2019 Active Directory Group Policy objects must have proper access control permissions. prevents CWE-1188

References