CVE-2026-55536Public exploitNetwork attack vector

Browser control via unanchored WebSocket Origin regex

Published Aug 25, 2026 · Updated Aug 28, 2026

Authentication bypass in PraisonAI before 4.6.58 allows remote attackers to control connected browsers via a forged WebSocket Origin. Browser Server _handle_connection() uses re.match() with an unanchored 32-character extension pattern, so Origins with trailing characters pass before websocket.accept(). The default listener is localhost-only; remote exploitation requires remote binding, while local processes or localhost SSRF can steal cookies or capture screenshots.

CVSS severity9.1
Critical
EPSS probability0.29%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Authentication bypass in PraisonAI before 4.6.58 allows remote attackers to control connected browsers via a forged WebSocket Origin. Browser Server _handle_connection() uses re.match() with an unanchored 32-character extension pattern, so Origins with trailing characters pass before websocket.accept(). The default listener is localhost-only; remote exploitation requires remote binding, while local processes or localhost SSRF can steal cookies or capture screenshots.

The record

CVE
CVE-2026-55536
Published
Aug 25, 2026
Updated
Aug 28, 2026
Vendor
PraisonAI
Product
PraisonAI
Classifications
CWE-625, CWE-284, T1539
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 25, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 28, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 4.6.58

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

PraisonAI · PraisonAIversion=< 4.6.58

Published CVSS scores

9.1GitHubCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-625Permissive Regular Expression
CWE-284Improper Access Control
T1539Steal Web Session Cookie

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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