CVE-2024-39943
Published: 04 July 2024
Summary
CVE-2024-39943 is a critical-severity OS Command Injection (CWE-78) vulnerability in Rejetto Http File Server. Its CVSS base score is 9.9 (Critical).
Operationally, ranked in the top 0.9% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.
Deeper analysis
CVE-2024-39943 affects rejetto HFS (HTTP File Server) version 3 prior to 0.52.10 running on Linux, UNIX, and macOS. The flaw is an OS command injection vulnerability (CWE-78) combined with improper access control (CWE-284) that stems from the use of Node.js child_process.execSync rather than spawnSync when invoking the df utility, allowing untrusted input to reach a system shell.
Remote authenticated users who possess Upload permissions can supply crafted input that results in arbitrary operating-system command execution with the privileges of the HFS process. The CVSS 3.1 base score of 9.9 reflects the combination of network attack vector, low complexity, and full confidentiality, integrity, and availability impact across the host.
Public references point to the official fix released in version 0.52.10; the associated GitHub commit and version diff replace the vulnerable execSync call, and the project wiki documents the upload-handling code paths that were previously exposed. The EPSS score currently stands at 0.7834 with no lower historical value reported.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2024-2262
Vulnerability details
rejetto HFS (aka HTTP File Server) 3 before 0.52.10 on Linux, UNIX, and macOS allows OS command execution by remote authenticated users (if they have Upload permissions). This occurs because a shell is used to execute df (i.e., with execSync…
more
instead of spawnSync in child_process in Node.js).
- CWE(s)
Related Threats
No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.
Affected Assets
Mitigating Controls
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.
Platform-independent apps typically execute inside a managed runtime or sandbox that restricts direct OS command execution, reducing the ability to exploit OS command injection.
The access control policy and procedures directly mandate and enforce proper access control mechanisms across the organization.
Device lock enforces restricted access until re-authentication, directly reducing unauthorized use of active sessions.
Supervision and review of access control activities directly detects and remediates improper access configurations or usages.
Explicitly identifying and documenting actions permitted without identification or authentication enforces proper access control boundaries by defining justified exceptions.
By automatically labeling outputs with security attributes, the control supports attribute-based enforcement and reduces exploitability of improper access control weaknesses.
Associating and retaining security attributes with data directly supports enforcement of access control decisions across storage, processing, and transmission.
Requiring prior authorization for each remote access type prevents improper access control over remote connections.