Description

A flaw has been found in mangroup dtale up to 3.22.0. This vulnerability affects the function build_secret_key of the file dtale/app.py of the component Flask Session Cookie. This manipulation causes insufficiently random values. Remote exploitation of the attack is possible. The attack's complexity is rated as high. It is stated that the exploitability is difficult. The exploit has been published and may be used. The pull request to fix this issue awaits acceptance.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "3.7",
  "pubDate": "2026-08-15T15:16:37.507Z",
  "pubdate": "2026-08-15T15:16:37.507Z",
  "executiveSummary": "An insufficient randomness vulnerability has been identified in the mangroup dtale application up to version 3.22.0. The security flaw specifically resides within the build_secret_key function located in the dtale/app.py file of the Flask Session Cookie component. This vulnerability leads to the generation of cryptographically weak or insufficiently random secret keys used for session management. Consequently, remote threat actors can potentially exploit this cryptographic weakness to compromise session integrity or forge session data.\nThe risk implications are significant, as remote exploitation of the attack is feasible, although the attack complexity is rated as high and exploitability is described as difficult. Publicly available exploit material currently exists, increasing the likelihood of opportunistic targeting. Organizations deploying vulnerable instances of mangroup dtale face potential unauthorized access or session manipulation if threat actors successfully reverse or predict the weak secret key generation mechanism.\nThe vulnerability affects all deployments utilizing mangroup dtale up to version 3.22.0 where the Flask Session Cookie component is active. While exploitation requires high complexity and is difficult to execute, the publication of a working exploit necessitates prompt defensive oversight and adherence to secure configuration management until an official patch is formally integrated and applied.",
  "technicalDetails": "The root cause of the vulnerability stems from the implementation of the build_secret_key function within the dtale/app.py file. This function is responsible for generating the cryptographic secret key utilized by the Flask Session Cookie component to sign and protect session data against tampering and forgery. Due to flawed logic or insufficient entropy sources within the key generation routine, the resulting secret keys fail to achieve the level of cryptographic randomness required for secure session management.\nThe vulnerable component is the Flask Session Cookie mechanism implemented in mangroup dtale up to version 3.22.0. The flaw is exposed remotely over the network, allowing external threat actors to interact with the application endpoint without requiring prior authentication or elevated privileges. Because the vulnerability relies on predictable or weakly generated secret keys, an attacker who analyzes the key generation parameters or captures sufficient session artifacts may theoretically deduce the secret key.\nThe attack flow begins with the threat actor observing or interacting with the dtale application to gather characteristics of the generated session cookies. Due to the high complexity and difficulty of exploitation, the attacker must expend computational resources or leverage the published exploit to analyze the weak entropy sources utilized by the build_secret_key function. Once the predictable key space is narrowed or successfully reverse-engineered, the attacker can forge valid cryptographic signatures for Flask session cookies.\nPost-exploitation impact includes the potential capability to bypass authentication controls, forge arbitrary session payloads, or manipulate session states depending on how the application processes the signed cookies. Because the secret key secures the integrity and confidentiality of the session data, successful key prediction undermines the entire session management architecture of the affected dtale deployment."
}