Cyber Resilience

CVE-2025-66518

Path Traversal in Apache Kyuubi 1.6.0 – 1.10.3

Published
05 January 2026
Modified
27 January 2026
CVSS Score v4 8.8
Click a component to see what it means
Raw vectorCVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:H/VI:H/VA:L/SC:H/SI:H/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS Score 0.0091 57th percentile
Risk Priority 55 floored blend · peak EPSS

Summary

CVE-2025-66518 is a high-severity Path Traversal: 'dir/../../filename' (CWE-27) vulnerability in Apache Kyuubi. Its CVSS base score is 8.8 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 43% 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 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-2025-66518 is a vulnerability in Apache Kyuubi that enables any client accessing the Apache Kyuubi Server via Kyuubi frontend protocols to bypass the server-side configuration kyuubi.session.local.dir.allow.list. This allows the client to use local files not listed in the configuration. The issue affects Apache Kyuubi versions from 1.6.0 through 1.10.2 and was published on 2026-01-05.

A low-privileged remote attacker (PR:L) with network access to the Kyuubi Server can exploit this vulnerability with low complexity and no user interaction required. The CVSS v3.1 base score of 8.8 (AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H) reflects high impacts on confidentiality, integrity, and availability. The flaw is linked to CWE-22 (Path Traversal) and CWE-27 (Relative Path Traversal), potentially allowing arbitrary local file access.

Apache advisories recommend upgrading to version 1.10.3 or later to remediate the issue. Additional details are available in the Apache mailing list thread at https://lists.apache.org/thread/xp460bwbyzdhho34ljd4nchyt2fmhodl and the OSS-Security announcement at http://www.openwall.com/lists/oss-security/2026/01/05/1.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Any client who can access to Apache Kyuubi Server via Kyuubi frontend protocols can bypass server-side config kyuubi.session.local.dir.allow.list and use local files which are not listed in the config. This issue affects Apache Kyuubi: from 1.6.0 through 1.10.2. Users are…

more

recommended to upgrade to version 1.10.3 or upper, which fixes the issue.

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-2026-62391Same product: Apache Kyuubi
CVE-2023-34478Same vendor: Apache
CVE-2025-66249Same vendor: Apache
CVE-2026-23907Same vendor: Apache
CVE-2023-22887Same vendor: Apache
CVE-2026-49818Same vendor: Apache
CVE-2026-33227Same vendor: Apache
CVE-2023-49735Same vendor: Apache
CVE-2026-33929Same vendor: Apache
CVE-2026-29220Same vendor: Apache

Affected Assets

apache
kyuubi
1.6.0 — 1.10.3

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • 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.

PR.PS-06 mostly match
prevents

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

ID.RA-01 partial match
prevents

Vulnerability identification processes will discover path traversal weaknesses during code or configuration review.

PR.AA-05 partial match
prevents

Least-privilege file permissions and access enforcement can limit the damage from a successful traversal.

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.

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

Secure coding standards require neutralizing '../' sequences and using safe file APIs, eliminating this exact weakness.

finds

Security testing in development catches path-traversal flaws before release but does not itself implement the control.

prevents

Secure development lifecycle mandates input validation and path sanitization that directly prevents directory traversal.

prevents

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

prevents

Secure architecture principles discourage unsafe path construction but do not prescribe the specific coding fix.

mitigates

Information access restriction can limit which files are reachable, reducing impact but not preventing the traversal vector.

References