Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:NSummary
CVE-2026-25992 is a high-severity Path Traversal (CWE-22) vulnerability in B3Log Siyuan. Its CVSS base score is 7.5 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 41th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
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.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
CVE-2026-25992 is a path traversal vulnerability (CWE-22) affecting SiYuan, an open-source personal knowledge management system, in versions prior to 3.5.5. The issue resides in the `/api/file/getFile` endpoint, which employs case-sensitive string equality checks to restrict access to sensitive files. On case-insensitive file systems like Windows, these checks can be bypassed by submitting requests with mixed-case paths, allowing unauthorized retrieval of protected configuration files.
The vulnerability carries a CVSS v3.1 base score of 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N), indicating it is exploitable over the network with low complexity and no authentication or user interaction required. Remote attackers can send crafted requests to the endpoint, leveraging the case-insensitivity mismatch to traverse path restrictions and disclose sensitive configuration data, potentially exposing user credentials, API keys, or other confidential information stored in the targeted files.
Mitigation is available in SiYuan version 3.5.5, which addresses the bypass by fixing the file access checks. Security practitioners should upgrade to this version immediately, as detailed in the project's release notes at https://github.com/siyuan-note/siyuan/releases/tag/v3.5.5 and the GitHub Security Advisory at https://github.com/siyuan-note/siyuan/security/advisories/GHSA-f72r-2h5j-7639. No workarounds are specified beyond updating.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-6758
Vulnerability Data
SiYuan is a personal knowledge management system. Prior to 3.5.5, the /api/file/getFile endpoint uses case-sensitive string equality checks to block access to sensitive files. On case-insensitive file systems such as Windows, attackers can bypass restrictions using mixed-case paths and read…
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protected configuration files. This vulnerability is fixed in 3.5.5.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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V5.3.2
Mitigating Controls (NIST 800-53 r5) AI
Enforces the intended directory access authorizations that path traversal would otherwise bypass.
Input validation directly neutralizes special path elements before pathname construction occurs.
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.
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 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.
Security testing in development catches path traversal via static/dynamic analysis.
Secure SDLC mandates input validation and path sanitization that directly prevent path traversal.
Application security requirements include rules for safe file handling and canonicalization.
Secure architecture principles require least-privilege file access and directory isolation.
Secure coding standards explicitly forbid unsafe path construction and mandate safe APIs.
Information access restriction limits which files an application may read or write.