CVE-2026-91944

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.

CVSS v3 6.1 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/unclecode/crawl4ai/security/advisories/GHSA-m446-hp3q-qfxp
https://www.vulncheck.com/advisories/crawl4ai-before-0.9.3-dom-based-xss-via-playground-ui

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-15 16:17

Updated : 2026-09-15 16:17

NVD link : CVE-2026-91944

Mitre link : CVE-2026-91944

CVE.ORG link : CVE-2026-91944

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

{"id": "CVE-2026-91944", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Primary", "source": "disclosure@vulncheck.com", "cvssData": {"scope": "CHANGED", "version": "3.1", "baseScore": 6.1, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N", "integrityImpact": "LOW", "userInteraction": "REQUIRED", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "LOW"}, "impactScore": 2.7, "exploitabilityScore": 2.8}], "cvssMetricV40": [{"type": "Secondary", "source": "disclosure@vulncheck.com", "cvssData": {"Safety": "NOT_DEFINED", "version": "4.0", "Recovery": "NOT_DEFINED", "baseScore": 5.1, "Automatable": "NOT_DEFINED", "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X", "exploitMaturity": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "userInteraction": "ACTIVE", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "subIntegrityImpact": "LOW", "vulnIntegrityImpact": "LOW", "integrityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "availabilityRequirement": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "subConfidentialityImpact": "LOW", "vulnConfidentialityImpact": "LOW", "confidentialityRequirement": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED"}}]}, "affected": [{"source": "disclosure@vulncheck.com", "affectedData": [{"vendor": "unclecode", "product": "crawl4ai", "versions": [{"status": "affected", "version": "0", "lessThan": "0.9.3", "versionType": "semver"}, {"status": "unaffected", "version": "0.9.3", "versionType": "semver"}], "packageURL": "pkg:pypi/crawl4ai", "defaultStatus": "unaffected"}]}], "published": "2026-09-15T16:17:46.433", "references": [{"url": "https://github.com/unclecode/crawl4ai/security/advisories/GHSA-m446-hp3q-qfxp", "source": "disclosure@vulncheck.com"}, {"url": "https://www.vulncheck.com/advisories/crawl4ai-before-0.9.3-dom-based-xss-via-playground-ui", "source": "disclosure@vulncheck.com"}], "vulnStatus": "Received", "weaknesses": [{"type": "Primary", "source": "disclosure@vulncheck.com", "description": [{"lang": "en", "value": "CWE-79"}]}], "descriptions": [{"lang": "en", "value": "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."}], "lastModified": "2026-09-15T16:17:46.433", "sourceIdentifier": "disclosure@vulncheck.com"}