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.
CVE-2026-55536
CRITICALPre-NVD 9.19.1
EchelonGraph scoreLOW confidence
This critical-severity CVE scores 9.1 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit-prediction score not yet available (the EPSS model rescores nightly; freshly-published CVEs typically appear within 48 hours). GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).
Triggered by: NVD CVSS baseline
Sources: secondary
9.1EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
- High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: —CVSS: 9.1Exploit: None knownExposed: 0
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 9.1
- EG Score
- 9.1(low)
- EG Risk
- 45(Track)EG Risk 45/100SSVC: Track
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity91% × 45%Exploitation0% × 40%Automatability30% × 15%Action: Routine — remediate on your standard cadence. - EPSS PROB
- —
- EPSS %ILE
- —
- KEV
- Not listed
Published
August 25, 2026
Last Modified
August 25, 2026
Advisory Details (3)
Auto-updated Aug 25, 2026🔬 Proof of concept available. Patch available. Sources: github, github_commit, github_release.
github_release Patch Available
PraisonAI v4.6.58
Patch available: MervinPraison/PraisonAI v4.6.58
https://github.com/MervinPraison/PraisonAI/releases/tag/v4.6.58github_commit Patch Available
commit 2f9677abb2ea (MervinPraison/PraisonAI)
Patch available: MervinPraison/PraisonAI v4.6.137 (contains commit 2f9677abb2ea)
https://github.com/MervinPraison/PraisonAI/commit/2f9677abb2ea68eab864ee8b6a828fd0141612e1github Patch Available🟡 PoC Available
Browser Server WebSocket origin validation bypass via unanchored regex (patch bypass of CVE-2026-40289 / GHSA-8x8f-54wf-vv92) · Advisory · MervinPraison/PraisonAI · GitHub
https://github.com/MervinPraison/PraisonAI/security/advisories/GHSA-6g6r-q6gw-w8fgVendor Advisories for CVE-2026-55536(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Weakness Classification(2)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 3× in last 7d / 3× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-08-25 16:24 UTCEG score recompute
- 2026-08-25 15:30 UTCEG score recompute
- 2026-08-25 15:29 UTCMITRE cvelistV5first tracked
Frequently asked(4)
What is CVE-2026-55536?
CVE-2026-55536 is a critical vulnerability published on August 25, 2026. PraisonAI is a multi-agent teams system. Prior to praisonai 4.6.58, Browser Server handleconnection() 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…
When was CVE-2026-55536 disclosed?
CVE-2026-55536 was first published in the National Vulnerability Database on August 25, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
What is the CVSS score of CVE-2026-55536?
CVE-2026-55536 has a CVSS v3 base score of 9.1 (NVD). The EG score is currently aggregating — additional source signals are being incorporated as they become available..
How do I remediate CVE-2026-55536?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-55536, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2026-55536
Is Your Infrastructure Affected by CVE-2026-55536?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.