EASY_CRAWL4AI

• Outcome: Review
• Latest audit: Sep 11, 2026 · 2:42 PM UTC
• Version: 1.0.0

Overview

This web-crawling skill has a clear purpose, but its command examples create avoidable risk by placing user-provided URLs and filenames directly into shell commands.

Review before installing. Use this only in an isolated environment, pin and verify dependencies, pass URLs as separate process arguments rather than shell strings, reject localhost/private/internal URLs, and restrict output files to a dedicated directory with generated or validated filenames.

A.I.G

Vulnerability Patterns

• Insecure Dependencies: Introduces malicious components through unsafe dependency sources
• Insecure Skill Coding Practices: Finds exploitable flaws such as hardcoded secrets or command injection
• Skill Instruction Hijacking: Alters the agent's session goals or safety constraints when the skill loads
• Agent Memory Poisoning: Writes attacker-controlled rules into memory that affect later sessions
• Remote Payload Retrieval and Execution: Fetches external code whose behavior can change after review

Findings (2)

T08 · Insecure Dependencies

Warning

• Location: SKILL.md:6
• Finding: Unpinned Third-Party Package Installation## Vulnerability Details **File Location**: `SKILL.md`, line 6 **Vulnerability Type**: Supply-chain exposure through an unpinned dependency **Risk Level**: Medium **Vulnerable Code Snippet**: ```bash pip3 install crawl4ai ``` ### Technical Analysis The installation instruction retrieves the latest available `crawl4ai` release without specifying an audited version or verifying package integrity. Consequently, the code installed at execution time can differ from the code that existed when the skill was reviewed. Package installation can execute package-controlled build or installation logic. A compromised upstream release, dependency compromise, or malicious package source configuration could therefore result in arbitrary code running locally. The instruction also does not require an isolated virtual environment or trusted package index. ### Attack Path 1. An attacker compromises the upstream package, one of its transitive dependencies, or a package source trusted by the local Python configuration. 2. A malicious release becomes the version selected by the unpinned installation command. 3. The agent follows the skill instructions and runs `pip3 install crawl4ai`. 4. Malicious installation logic or installed package code executes under the identity running the agent. 5. The payload can access resources available to that account and may modify the Python environment or other user-writable files. ### Impact Assessment Successful exploitation could provide arbitrary code execution with the privileges of the account performing the installation. The affected scope includes that account's files, environment variables, accessible credentials, Python environment, and network permissions. System-wide impact would require the command to be run with elevated privileges, which the skill does not explicitly request.
• Remediation: ## Remediation Suggestions - Pin `crawl4ai` and all transitive dependencies to reviewed versions in a lock file. - Require package hashes, such as through `pip install --require-hashes -r requirements.txt`. - Install only from an explicitly trusted package index. - Perform installation inside a dedicated, least-privileged virtual environment or container. - Review dependency changes and scan packages before updating locked versions. - Avoid running package installation commands as root or with administrative privileges.

T09 · Insecure Skill Coding Practices

Error

• Location: SKILL.md:23
• Finding: Shell Command Injection Through Unquoted URL and Filename Placeholders## Vulnerability Details **File Location**: `SKILL.md`, lines 23-28; equivalent command templates also appear at lines 36-37 **Vulnerability Type**: Shell command injection **Risk Level**: High **Vulnerable Code Snippet**: ```bash crwl {url} -o markdown ``` ```bash crwl {url} -o markdown > {file_name}.md ``` The same unsafe patterns are demonstrated in the usage table: ```bash crwl {URL} -o markdown crwl {URL} -o markdown > article.md ``` ### Technical Analysis The command templates place a user-provided URL directly into a shell command without quoting, validation, or argument separation. The file-writing template likewise places a filename into a shell redirection expression without constraining or escaping it. If the agent substitutes attacker-controlled content and invokes the resulting string through a shell, shell metacharacters such as semicolons, command substitutions, pipes, redirections, or newlines can terminate or alter the intended `crwl` invocation. A crafted value can then introduce additional local commands. A filename may also contain traversal components or absolute paths, potentially causing output to overwrite unintended user-writable files even when command metacharacters are rejected. ### Attack Path 1. An attacker supplies a URL or requested output filename containing shell syntax, such as a semicolon followed by another command. 2. The agent substitutes that value into the documented command template without validation or shell-safe argument handling. 3. The resulting command string is passed to a shell. 4. The shell interprets the injected metacharacters rather than treating the entire value as a single URL or filename. 5. The injected command executes with the agent process's privileges. 6. For filename abuse, the attacker may alternatively use path traversal or an absolute path to overwrite an accessible file. Exploitation depends on the agent executing these template ...[truncated 712 chars]
• Remediation: ## Remediation Suggestions - Do not construct shell command strings from user-controlled values. - Invoke `crwl` through a process API using a fixed argument array, for example arguments equivalent to `["crwl", validated_url, "-o", "markdown"]`, with shell processing disabled. - Parse URLs with a URL library and allow only required schemes such as `https`; reject control characters, whitespace, and unsupported schemes. - Treat values beginning with `-` carefully so that they cannot be interpreted as command-line options; use an end-of-options marker if supported. - Generate output filenames internally rather than accepting arbitrary paths. - If filenames must be user-selected, restrict them to a conservative allowlist, resolve the final path, and verify that it remains inside a dedicated output directory. - Create output files through application file APIs rather than shell redirection. - Run the crawler with least privilege and restrict filesystem and network access where practical.

SkillSpector

Vulnerability Patterns

• Trigger Abuse: Overly Broad Trigger, Shadow Command Trigger, Keyword Baiting Trigger
• Prompt Injection: Instruction Override, Hidden Instructions, Exfiltration Commands
• Data Exfiltration: External Transmission, Env Variable Harvesting, File System Enumeration
• Privilege Escalation: Excessive Permissions, Sudo/Root Execution, Credential Access
• Supply Chain: Unpinned Dependencies, External Script Fetching, Obfuscated Code

Findings (2)

Natural-Language Policy Violations

Medium

• Confidence: 91% confidence
• Finding: The natural-language instructions and usage guidance are written in Chinese throughout the file, but there is no statement offering a language choice or explaining that the skill is intended only for a Chinese-speaking or region-specific context. Under the policy, forcing a specific language without user opt-in is a locale/language policy concern.

Vague Triggers

Medium

• Confidence: 93% confidence
• Finding: The trigger condition activates on very broad user intents like 'summarize content', 'extract data', or 'analyze webpage' whenever a URL is present. This can cause the skill to run in contexts the user did not clearly intend, leading the agent to fetch untrusted external content, potentially exposing the environment to SSRF-like access patterns, unexpected network activity, or processing of adversarial pages.

Static analysis

No suspicious patterns detected.