xxe
Hunt XML External Entity flaws in parsers and validate file read / SSRF impact with strict negative controls.
60
70%
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Critical
Do not install without reviewing
Fix and improve this skill with Tessl
tessl review fix ./packages/decepticon/decepticon/skills/standard/analyst/xxe/SKILL.mdSecurity
3 findings: 1 critical severity, 1 high severity, 1 medium severity. Installing this skill is not recommended: please review these findings carefully if you do intend to do so.
E006: Malicious code pattern detected in skill scripts.
What this means
Detected high-risk code patterns in the skill content — including its prompts, tool definitions, and resources — such as data exfiltration, backdoors, remote code execution, credential theft, system compromise, supply chain attacks, and obfuscation techniques.
Why it was flagged
This document is an explicit playbook for exploiting XXE vulnerabilities (finder sinks, enabling dangerous defaults, payloads to read files and perform SSRF), which indicates clear malicious intent to exfiltrate data and interact with internal services.
W007: Insecure credential handling detected in skill instructions.
What this means
The skill handles credentials insecurely by requiring the agent to include secret values verbatim in its generated output. This exposes credentials in the agent’s context and conversation history, creating a risk of data exfiltration.
Why it was flagged
The playbook explicitly instructs crafting XXE payloads to read local files (e.g., /etc/passwd) and internal metadata and to validate by checking/returning parser output containing file or internal response contents, which requires the agent to handle/exfiltrate secret values verbatim.
W013: Attempt to modify system services in skill instructions.
What this means
The skill prompts the agent to compromise the security or integrity of the user’s machine by modifying system-level services or configurations, such as obtaining elevated privileges, altering startup scripts, or changing system-wide settings.
Why it was flagged
The skill explicitly instructs exploiting XXE to read local system files (e.g., file:///etc/passwd) and perform SSRF to internal services, which can compromise the host's confidentiality and possibly its operation.
- Repository
- PurpleAILAB/Decepticon
- Commit
e34afba
- Audited
- Security analysis
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