Vulnerability · Published Sep 15, 2026 · Assigned by VulnCheck

CVE-2026-91944crawl4ai before 0.9.3 DOM-based XSS via Playground UI

Medium 6.1

In plain English

A medium-severity cross-site scripting in crawl4ai from unclecode. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 18% of all known vulnerabilities).

Severity (CVSS 3.1)6.1Medium

Exploit odds (30 days)0.3%top 81.8% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

crawl4ai versions before 0.9.3 contain a DOM-based cross-site scripting vulnerability in the Playground UI where the forceHighlightElement() function assigns textContent back to innerHTML, re-parsing JSON responses as HTML. Attackers can inject malicious scripts through crawled page content like the page title to steal the operator's API token from sessionStorage and gain full server control.

Affected products (as reported)

Vendor	Product	Versions
unclecode	crawl4ai	0 – before 0.9.3

Weakness: CWE-79 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

References

GitHub Security Advisory (GHSA-m446-hp3q-qfxp) vendor-advisory
VulnCheck Advisory: crawl4ai before 0.9.3 DOM-based XSS via Playground UI third-party-advisory