Improper Access Control in Message Handler Parameter Validation

A vulnerability was found in OpenBMB Internet of Agents up to 9d78e88e47160eb42ee1ee8538c05e1c2c47877a. This issue affects the function fetch_chat_record of the file im_server/app.py of the component Message Handler. The manipulation of the argument comm_id results in improper access controls. The attack may be performed from remote. The exploit has been made public and could be used. The project was informed of the problem early through an issue report but has not responded yet.

Casky was already ahead

This CVE exploits attack patterns that Casky's 224matched skills already investigate — long before this vulnerability was disclosed. Claude's reasoning model maps these techniques to MITRE ATT&CK, so practitioners who ran these skills have already seen the threat behaviour in their findings.

Analysis

OpenBMB's Internet of Agents contains an improper access control vulnerability in the Message Handler component where the fetch_chat_record function fails to adequately validate the comm_id parameter. This allows remote attackers to bypass authorization checks and access message records they should not have permission to view. The vulnerability affects versions up to commit 9d78e88e47160eb42ee1ee8538c05e1c2c47877a and is particularly concerning because it enables unauthorized data disclosure in agent communication systems—environments where sensitive conversations and interactions occur. Any organization deploying OpenBMB for multi-agent messaging or collaborative AI systems faces immediate risk of information exposure without proper patching.

Casky's 224 matched security skills detect this vulnerability pattern by analyzing TA0004 (Privilege Escalation) techniques through Claude AI's extended reasoning capabilities. Practitioners would identify this attack through skills focused on access control validation failures and parameter tampering detection—specifically observing anomalous fetch_chat_record requests with manipulated comm_id values that deviate from expected authorization boundaries. The platform's skill mapping reveals how attackers leverage improper input validation (CWE-266, CWE-284) to escalate from unauthenticated or low-privilege access to unauthorized data retrieval. Findings would highlight requests accessing comm_id values outside the requestor's legitimate scope, suspicious patterns of sequential ID enumeration, and API calls bypassing the expected authorization framework—enabling teams to rapidly correlate detection signals and implement targeted mitigations before exploitation.

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Casky Risk Score

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EPSS Probability

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Shodan Exposure

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GreyNoise Signal

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224 Casky skills cover this attack pattern

These skills use Claude AI's reasoning model to surface findings in the same attack categories as CVE-2026-123881.

abusing-dpapi-for-credential-access

red teaming · high

Run

abusing-shadow-credentials-for-privesc

red teaming · high

Run

Access with Stolen Session Cookie

identity access management · low

Run

MITRE ATT&CK Techniques

TA0004

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