Cyber Resilience

CVE-2020-37041

HighPublic PoC

Published: 30 January 2026

Published
30 January 2026
Modified
13 February 2026
KEV Added
Patch
CVSS Score v4 7.1 CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/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 0.0040 61.2th percentile
Risk Priority 14 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2020-37041 is a high-severity Path Traversal (CWE-22) vulnerability in Citeum Opencti. Its CVSS base score is 7.1 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 38.8% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified are NIST 800-53 SI-10 (Information Input Validation) and AC-22 (Publicly Accessible Content).

Deeper analysis

CVE-2020-37041 is a directory traversal vulnerability in OpenCTI version 3.3.1, specifically affecting the static/css endpoint. An unauthenticated attacker can read arbitrary files from the filesystem by sending crafted GET requests containing path traversal sequences such as '../' in the URL. For example, a request to /static/css//../../../../../../../../etc/passwd returns the contents of /etc/passwd. The vulnerability, discovered by Raif Berkay Dincel, was confirmed on Linux Mint and Windows 10, with a CVSS score of 7.5 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N) and mapped to CWE-22.

An unauthenticated attacker can exploit this vulnerability remotely with low attack complexity, no privileges, and no user interaction required. Successful exploitation grants high confidentiality impact by allowing access to sensitive files on the server, such as configuration files or password lists, while causing no integrity or availability disruption.

Advisories and related resources, including the OpenCTI GitHub repository (https://github.com/OpenCTI-Platform/opencti), an Exploit-DB entry (https://www.exploit-db.com/exploits/48595), the OpenCTI website (https://www.opencti.io/), and a Vulncheck advisory (https://www.vulncheck.com/advisories/opencti-directory-traversal), provide further details on patches and mitigation.

EU & UK References

Vulnerability details

OpenCTI 3.3.1 is vulnerable to a directory traversal attack via the static/css endpoint. An unauthenticated attacker can read arbitrary files from the filesystem by sending crafted GET requests with path traversal sequences (e.g., '../') in the URL. For example, requesting…

more

/static/css//../../../../../../../../etc/passwd returns the contents of /etc/passwd. This vulnerability was discovered by Raif Berkay Dincel and confirmed on Linux Mint and Windows 10.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

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.
Why these techniques?

Directory traversal in public web endpoint enables remote unauthenticated file read from local system (e.g. /etc/passwd).

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1

CVEs Like This One

CVE-2026-21887Same product: Citeum Opencti
CVE-2026-27960Same product: Citeum Opencti
CVE-2026-44730Same product: Citeum Opencti
CVE-2026-21886Same product: Citeum Opencti
CVE-2025-61781Same product: Citeum Opencti
CVE-2026-39980Same product: Citeum Opencti
CVE-2025-12824Shared CWE-22
CVE-2026-25965Shared CWE-22
CVE-2025-30567Shared CWE-22
CVE-2025-27098Shared CWE-22

Affected Assets

citeum
opencti
3.3.1

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly mitigates directory traversal by requiring effective input validation on URL entry points to reject path traversal sequences like '../'.

prevent

Requires design and maintenance of publicly accessible endpoints like static/css to protect against unauthorized access to non-public filesystem content.

prevent

Enforces application-level access controls to restrict file reads to authorized paths only, blocking traversal to arbitrary sensitive files.

References