What’s Vulnerable › Vulnerabilities

CVE-2026-55536: Browser Server WebSocket origin validation bypass via unanchored regex (patch bypass of CVE-2026-40289 / GHSA-8x8f-54wf-vv92)

• Severity: critical (CVSS 9.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.5% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-08-25 · updated 2026-09-09
• Weakness: CWE-284

Description

PraisonAI is a multi-agent teams system. Prior to praisonai 4.6.58, Browser Server _handle_connection() checks Chrome extension origins with re.match() and the unanchored expression chrome-extension://[a-z0-9]{32}. Extra trailing characters pass before websocket.accept(), allowing start_session commands and unauthorized browser automation. This issue is fixed in version 4.6.58.

Affected products

• MervinPraison PraisonAI: before 4.6.58

References

• https://github.com/MervinPraison/PraisonAI/commit/2f9677abb2ea68eab864ee8b6a828fd0141612e1
• https://github.com/MervinPraison/PraisonAI/releases/tag/v4.6.58
• https://github.com/MervinPraison/PraisonAI/security/advisories/GHSA-6g6r-q6gw-w8fg
• https://github.com/MervinPraison/PraisonAI/security/advisories/GHSA-6g6r-q6gw-w8fg

Get alerted when CVE-2026-55536 or the next vulnerability affects your stack