Answer in brief
CVE-2026-55536 records a Critical severity (CVSS 9.1) vulnerability in Browser Server WebSocket origin validation bypass via unanchored regex (patch bypass of CVE-2026-40289 / GHSA-8x8f-54wf-vv92). The current sources do not mark it as known exploited. The current feed maps MervinPraison/PraisonAI (generic), PraisonAI (pip), praisonai (pypi). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 9.1. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps MervinPraison/PraisonAI (generic), PraisonAI (pip), praisonai (pypi). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| MervinPraison/PraisonAIgeneric | < 4.6.58 | Not reported |
| PraisonAIpip | <4.6.58 | 4.6.58 |
| praisonaipypi | >=0 <4.6.58 | 4.6.58 |
Published upstream
Aug 25, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Sep 9, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 25, 2026
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.
Quoted source text, attributed separately from HOL analysis.