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Security audit

Sendbird

Security checks for vulnerabilities and agentic risk

Overview

The Sendbird workflow has clear approval controls, but its fallback setup runs an unverified remote installer without a separate approval step.

Review and approve CLI installation separately before allowing the missing-command fallback. Check its settings for installing or synchronizing other agent skills, use narrowly scoped Sendbird access, and retain the documented confirmations for changes and deletions. OOMOL mediates the connection; its remote installer and hosted connector were not audited here. No artifact-backed malicious behavior was found.

Vulnerability Patterns
  • Skill Instruction HijackingAlters the agent's session goals or safety constraints when the skill loads
  • Agent Memory PoisoningWrites attacker-controlled rules into memory that affect later sessions
  • Remote Payload Retrieval and ExecutionFetches external code whose behavior can change after review
  • Embedded Malicious CodeShips malicious scripts inside the skill and executes them locally
  • Unauthorized Access and Privilege EscalationObtains permissions beyond the task's legitimate needs
Vulnerability Patterns
  • Supply ChainUnpinned Dependencies, External Script Fetching, Obfuscated Code
  • Excessive AgencyUnrestricted Tool Access, Autonomous Decision Making, Scope Creep
  • Output HandlingUnvalidated Output Injection, Cross-Context Output, Unbounded Output
  • MCP Tool PoisoningHidden Instructions, Unicode Deception, Parameter Description Injection
  • Prompt InjectionInstruction Override, Hidden Instructions, Exfiltration Commands
Findings (4)

Description-Behavior Mismatch

High
Category
MCP Tool Poisoning
Confidence
97% confidence
Finding

The supplied code installs software from an Oomol domain rather than performing Sendbird operations. No visible code establishes that this installer is a supporting dependency for the declared purpose. The remote script's contents and subsequent behavior cannot be determined from this chunk.

Content

No source excerpt is available for this finding.

External Script Fetching

High
Category
Supply Chain
Confidence
98% confidence
Finding

The command executes a remotely fetched, mutable script directly in a local shell without version pinning or independent integrity verification; the PowerShell alternative uses the same fetch-and-execute pattern. If the distribution endpoint or delivery pipeline is compromised, attacker-controlled code could run with the invoking user's permissions, although the vendor-related URL and missing-CLI prerequisite make this a supply-chain exposure rather than evidence of intentional exfiltration.

Content

Scanner excerpt · SKILL.md (reported line 82)May include surrounding context.

Fallback setup executes downloaded installation scripts without warning about local system changes.

Medium
Category
Output Handling
Confidence
91% confidence
Finding

The missing-command fallback directs the agent to install software without explicitly obtaining approval for local system changes. Installation is relevant to the task and conditional, which reduces concern about malicious intent, but permission to operate Sendbird does not necessarily authorize modifying the host; the declared oo-only tool restriction may also prevent these commands in a strictly enforced environment.

Content

No source excerpt is available for this finding.

Autonomous Decision Making

Medium
Category
Excessive Agency
Confidence
80% confidence
Finding

Skill enables autonomous high-impact decisions without human-in-the-loop verification. Critical operations (destructive commands, financial transactions, data deletion) should require explicit user confirmation.

Content

Scanner excerpt · SKILL.md (reported line 103)May include surrounding context.

md
- **`OOMOL_INSUFFICIENT_CREDIT`** — OOMOL billing stop. Recharge at `https://console.oomol.com/billing/token-recharge` before retrying.

- **HTTP 402 without `OOMOL_INSUFFICIENT_CREDIT`** — the third-party account itself has no active plan or credit. Report the provider error message as is; do not ask the user to recharge OOMOL.

## Resources