Cyber Resilience

CVE-2023-39916

Path Traversal in Nlnetlabs Routinator 0.9.0 – 0.12.2

Published
13 September 2023
Modified
03 October 2025
Patch / advisory
CVSS Score v3.1 9.3
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:H/A:H
EPSS Score 0.0055 43th percentile
Risk Priority 66 floored blend · peak EPSS

Summary

CVE-2023-39916 is a critical-severity Path Traversal: '.../...//' (CWE-35) vulnerability in Nlnetlabs Routinator. Its CVSS base score is 9.3 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 43th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

NLnet Labs’ Routinator 0.9.0 up to and including 0.12.1 as well as 0.14.0 up to and including 0.14.2 contains a possible path traversal vulnerability in the optional, off-by-default keep-rrdp-responses feature that allows users to store the content of responses received…

more

for RRDP requests. The location of these stored responses is constructed from the URL of the request. Due to insufficient sanitation of the URL, it is possible for an attacker to craft a URL that results in the response being stored outside of the directory specified for it.

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.
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.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-49233Same product: Nlnetlabs Routinator
CVE-2024-0067Shared CWE-22, CWE-35
CVE-2024-2654Shared CWE-22, CWE-35
CVE-2025-41736Shared CWE-22, CWE-35
CVE-2023-21418Shared CWE-22, CWE-35
CVE-2025-40573Shared CWE-22, CWE-35
CVE-2024-49770Shared CWE-22, CWE-35
CVE-2023-5885Shared CWE-22, CWE-35
CVE-2025-26935Shared CWE-22, CWE-35
CVE-2025-27222Shared CWE-22, CWE-35

Affected Assets

nlnetlabs
routinator
0.9.0 — 0.12.2

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

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-22

Validates pathnames and filenames to prevent traversal outside intended directories.

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 neutralize traversal sequences.

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 can detect path-traversal flaws before release.

prevents

Secure SDLC mandates input validation and path-handling controls that directly mitigate path traversal.

prevents

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

prevents

Secure architecture principles require proper directory restrictions and input sanitization to prevent traversal.

prevents

Secure coding standards explicitly forbid unsafe path concatenation and mandate canonicalization routines.

mitigates

Information access restriction limits file reachability but does not address the input-validation flaw itself.

References