Is CVE-2026-91942 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-91942 being exploited in the wild.

How severe is CVE-2026-91942?

Medium severity, with a CVSS score of 5.4, published 15 September 2026.

Which products and versions are affected?

unclecode crawl4ai before 0.9.3.

Is there a fix for CVE-2026-91942?

A patch was published on 2026-08-31: Patched in version 0.9.3 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-91942 attacked?

It is attacked over the network.

Am I affected by CVE-2026-91942?

Check whether anything you run is named in the advisory. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-91942: crawl4ai DOM-based XSS in Docker Playground via innerHTML

CVE-2026-91942 · Severity: medium · CVSS 5.4 · Published 2026-09-15

crawl4ai is a web scraping tool whose Docker Playground UI allows operators to view crawl results interactively. A vulnerability in the Playground displays untrusted crawl output (such as text from PDFs) as HTML without sanitization, allowing an attacker to inject malicious JavaScript. An attacker who controls a target website or PDF can execute code in the Playground, stealing the operator's API authentication token and hijacking their API access.

Quick answers

Is CVE-2026-91942 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-91942 being exploited in the wild.
How severe is CVE-2026-91942?: Medium severity, with a CVSS score of 5.4, published 15 September 2026.
Which products and versions are affected?: unclecode crawl4ai before 0.9.3.
Is there a fix for CVE-2026-91942?: A patch was published on 2026-08-31: Patched in version 0.9.3 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-91942 attacked?: It is attacked over the network.
Am I affected by CVE-2026-91942?: Check whether anything you run is named in the advisory. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

The vulnerability is a DOM-based XSS (CWE-79) arising from two combined issues. First, the Playground UI's forceHighlightElement() function reads text from DOM elements and assigns it to element.innerHTML, re-parsing it as HTML rather than treating it as plain text. Second, the PDF text extraction pipeline in crawl4ai/processors/pdf/utils.py wraps paragraph text in <p> tags without HTML-escaping, allowing malicious markup to pass through unescaped. An attacker can craft a malicious PDF containing event-handler elements (e.g., <img onerror=...>) that execute JavaScript when an operator views the result in the Playground. The injected script runs in the Playground origin and can read the API token from sessionStorage, enabling authenticated API abuse. Interaction is required: the operator must view the malicious crawl result. Patches are available in version 0.9.3 and later.

Affected products

unclecode crawl4ai before 0.9.3

Timeline

2026-08-31: disclosed: GHSA-7g3g-vhm6-79f3 published on GitHub
2026-09-15: advisory: CVE-2026-91942 published on NVD
2026-08-31: patched: Patched in version 0.9.3

References

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