---
id: CVE-2026-78381
title: >-
  RansomLook contains a path traversal vulnerability in the handling of the
  screen field associated with group posts
summary: >-
  RansomLook contains a path traversal vulnerability in the handling of the
  screen field associated with group posts. The GroupPost.get API handler
  concatenates the database-controlled screen value directly with the
  application's source/ d…
severity: none
cwe:
  - CWE-22
published: '2026-08-24'
updated: '2026-10-14'
sourceUpdated: '2026-10-14T13:10:00.187'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-78381'
references:
  - url: >-
      https://github.com/RansomLook/RansomLook/commit/274faccf65898e88ef54f35f304e0821a852a0b8
    label: 5a6e4751-2f3f-4070-9419-94fb35b644e8
tags:
  - nvd
epss: 0.00588
epssPercentile: 0.46667
ingestedAt: '2026-10-14T13:30:58.560Z'
---

## Overview

RansomLook contains a path traversal vulnerability in the handling of the screen field associated with group posts. The GroupPost.get API handler concatenates the database-controlled screen value directly with the application's source/ directory and opens the resulting path without verifying that the resolved file remains within the intended directory.

Because the screen field is free-form and can be populated either through the administrative post editor or through data imported from a remote RansomLook instance, a malicious upstream instance can provide traversal sequences such as ../config/generic.json. When the affected post is subsequently retrieved through the API, RansomLook resolves and reads the attacker-controlled path and returns the contents of the referenced file Base64-encoded in the API response.

This can allow an attacker (being admin) controlling imported post data to read arbitrary files accessible to the RansomLook process, potentially exposing sensitive configuration data, API credentials, password hashes, or other application secrets. The attack does not require the malicious upstream to possess an account on the affected RansomLook instance.

The vulnerability is addressed by resolving screen paths with os.path.realpath() and verifying that the resolved path remains beneath the application's source/ directory. Validation is performed both when values are written and immediately before files are read. Using canonical paths also prevents traversal through symbolic links that would bypass purely lexical path normalization checks.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.