Update Apache_httpd importer from XML to JSON Advisory (#425)

* Update Apache httpd importer from importing XML to JSON data

Signed-off-by: AmitGupta7580 <amitgupta758000@gmail.com>

Author: AmitGupta7580

vulnerabilities/importers/apache_httpd.py

@@ -20,16 +20,25 @@
 #  VulnerableCode is a free software tool from nexB Inc. and others.
 #  Visit https://github.com/nexB/vulnerablecode/ for support and download.
 
+import asyncio
 import dataclasses
-from xml.etree import ElementTree
+import urllib
 
 import requests
+from bs4 import BeautifulSoup
 from packageurl import PackageURL
+from univers.versions import MavenVersion
+from univers.version_specifier import VersionSpecifier
 
 from vulnerabilities.data_source import Advisory
 from vulnerabilities.data_source import DataSource
 from vulnerabilities.data_source import DataSourceConfiguration
+from vulnerabilities.data_source import Reference
+from vulnerabilities.data_source import VulnerabilitySeverity
+from vulnerabilities.package_managers import GitHubTagsAPI
+from vulnerabilities.severity_systems import scoring_systems
 from vulnerabilities.helpers import create_etag
+from vulnerabilities.helpers import nearest_patched_package
 
 
 @dataclasses.dataclass
@@ -40,56 +49,113 @@ class ApacheHTTPDDataSourceConfiguration(DataSourceConfiguration):
 class ApacheHTTPDDataSource(DataSource):
 
     CONFIG_CLASS = ApacheHTTPDDataSourceConfiguration
-    url = "https://httpd.apache.org/security/vulnerabilities-httpd.xml"
+    base_url = "https://httpd.apache.org/security/json/"
+
+    def set_api(self):
+        self.version_api = GitHubTagsAPI()
+        asyncio.run(self.version_api.load_api(["apache/httpd"]))
 
     def updated_advisories(self):
-        # Etags are like hashes of web responses. We maintain
-        # (url, etag) mappings in the DB. `create_etag`  creates
-        # (url, etag) pair. If a (url, etag) already exists then the code
-        # skips processing the response further to avoid duplicate work
-
-        if create_etag(data_src=self, url=self.url, etag_key="ETag"):
-            data = fetch_xml(self.url)
-            advisories = to_advisories(data)
-            return self.batch_advisories(advisories)
-
-        return []
-
-
-def to_advisories(data):
-    advisories = []
-    for issue in data:
-        resolved_packages = []
-        impacted_packages = []
-        for info in issue:
-            if info.tag == "cve":
-                cve = info.attrib["name"]
-
-            if info.tag == "title":
-                summary = info.text
-
-            if info.tag == "fixed":
-                resolved_packages.append(
-                    PackageURL(type="apache", name="httpd", version=info.attrib["version"])
+        links = fetch_links(self.base_url)
+        self.set_api()
+        advisories = []
+        for link in links:
+            data = requests.get(link).json()
+            advisories.append(self.to_advisory(data))
+        return self.batch_advisories(advisories)
+
+    def to_advisory(self, data):
+        cve = data["CVE_data_meta"]["ID"]
+        descriptions = data["description"]["description_data"]
+        description = None
+        for desc in descriptions:
+            if desc["lang"] == "eng":
+                description = desc.get("value")
+                break
+
+        severities = []
+        impacts = data.get("impact", [])
+        for impact in impacts:
+            value = impact.get("other")
+            if value:
+                severities.append(
+                    VulnerabilitySeverity(
+                        system=scoring_systems["apache_httpd"],
+                        value=value,
+                    )
                 )
+                break
+        reference = Reference(
+            reference_id=cve,
+            url=urllib.parse.urljoin(self.base_url, f"{cve}.json"),
+            severities=severities,
+        )
 
-            if info.tag == "affects" or info.tag == "maybeaffects":
-                impacted_packages.append(
-                    PackageURL(type="apache", name="httpd", version=info.attrib["version"])
-                )
+        versions_data = []
+        for vendor in data["affects"]["vendor"]["vendor_data"]:
+            for products in vendor["product"]["product_data"]:
+                for version_data in products["version"]["version_data"]:
+                    versions_data.append(version_data)
 
-        advisories.append(
-            Advisory(
-                vulnerability_id=cve,
-                summary=summary,
-                impacted_package_urls=impacted_packages,
-                resolved_package_urls=resolved_packages,
+        fixed_version_ranges, affected_version_ranges = self.to_version_ranges(versions_data)
+
+        affected_packages = []
+        fixed_packages = []
+
+        for version_range in fixed_version_ranges:
+            fixed_packages.extend(
+                [
+                    PackageURL(type="apache", name="httpd", version=version)
+                    for version in self.version_api.get("apache/httpd")
+                    if MavenVersion(version) in version_range
+                ]
             )
+
+        for version_range in affected_version_ranges:
+            affected_packages.extend(
+                [
+                    PackageURL(type="apache", name="httpd", version=version)
+                    for version in self.version_api.get("apache/httpd")
+                    if MavenVersion(version) in version_range
+                ]
+            )
+
+        return Advisory(
+            vulnerability_id=cve,
+            summary=description,
+            affected_packages=nearest_patched_package(affected_packages, fixed_packages),
+            references=[reference],
         )
 
-    return advisories
+    def to_version_ranges(self, versions_data):
+        fixed_version_ranges = []
+        affected_version_ranges = []
+        for version_data in versions_data:
+            version_value = version_data["version_value"]
+            range_expression = version_data["version_affected"]
+            if range_expression == "<":
+                fixed_version_ranges.append(
+                    VersionSpecifier.from_scheme_version_spec_string(
+                        "maven", ">={}".format(version_value)
+                    )
+                )
+            elif range_expression == "=" or range_expression == "?=":
+                affected_version_ranges.append(
+                    VersionSpecifier.from_scheme_version_spec_string(
+                        "maven", "{}".format(version_value)
+                    )
+                )
+
+        return (fixed_version_ranges, affected_version_ranges)
 
 
-def fetch_xml(url):
-    resp = requests.get(url).content
-    return ElementTree.fromstring(resp)
+def fetch_links(url):
+    links = []
+    data = requests.get(url).content
+    soup = BeautifulSoup(data, features="lxml")
+    for tag in soup.find_all("a"):
+        link = tag.get("href")
+        if not link.endswith("json"):
+            continue
+        links.append(urllib.parse.urljoin(url, link))
+    return links

vulnerabilities/severity_systems.py

@@ -87,4 +87,9 @@ def as_score(self, value):
         url="",
         notes="Severity for unknown scoring systems. Contains generic textual values like High, Low etc",
     ),
+    "apache_httpd": ScoringSystem(
+        identifier="apache_httpd",
+        name="Apache Httpd Severity",
+        url="https://httpd.apache.org/security/impact_levels.html",
+    ),
 }

vulnerabilities/tests/test_apache_httpd.py

@@ -0,0 +1,124 @@
+# Copyright (c) nexB Inc. and others. All rights reserved.
+# http://nexb.com and https://github.com/nexB/vulnerablecode/
+# The VulnerableCode software is licensed under the Apache License version 2.0.
+# Data generated with VulnerableCode require an acknowledgment.
+#
+# You may not use this software except in compliance with the License.
+# You may obtain a copy of the License at: http://apache.org/licenses/LICENSE-2.0
+# Unless required by applicable law or agreed to in writing, software distributed
+# under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
+# CONDITIONS OF ANY KIND, either express or implied. See the License for the
+# specific language governing permissions and limitations under the License.
+#
+# When you publish or redistribute any data created with VulnerableCode or any VulnerableCode
+# derivative work, you must accompany this data with the following acknowledgment:
+#
+#  Generated with VulnerableCode and provided on an "AS IS" BASIS, WITHOUT WARRANTIES
+#  OR CONDITIONS OF ANY KIND, either express or implied. No content created from
+#  VulnerableCode should be considered or used as legal advice. Consult an Attorney
+#  for any legal advice.
+#  VulnerableCode is a free software from nexB Inc. and others.
+#  Visit https://github.com/nexB/vulnerablecode/ for support and download.
+
+import os
+import json
+from unittest import TestCase
+
+from packageurl import PackageURL
+from univers.version_specifier import VersionSpecifier
+
+from vulnerabilities.data_source import Reference
+from vulnerabilities.data_source import Advisory
+from vulnerabilities.data_source import VulnerabilitySeverity
+from vulnerabilities.package_managers import GitHubTagsAPI
+from vulnerabilities.severity_systems import scoring_systems
+from vulnerabilities.importers.apache_httpd import ApacheHTTPDDataSource
+from vulnerabilities.helpers import AffectedPackage
+
+BASE_DIR = os.path.dirname(os.path.abspath(__file__))
+TEST_DATA = os.path.join(BASE_DIR, "test_data", "apache_httpd", "CVE-1999-1199.json")
+
+
+class TestApacheHTTPDDataSource(TestCase):
+    @classmethod
+    def setUpClass(cls):
+        data_source_cfg = {"etags": {}}
+        cls.data_src = ApacheHTTPDDataSource(1, config=data_source_cfg)
+        known_versions = ["1.3.2", "1.3.1", "1.3.0"]
+        cls.data_src.version_api = GitHubTagsAPI(cache={"apache/httpd": known_versions})
+        with open(TEST_DATA) as f:
+            cls.data = json.load(f)
+
+    def test_to_version_ranges(self):
+        data = [
+            {
+                "version_affected": "?=",
+                "version_value": "1.3.0",
+            },
+            {
+                "version_affected": "=",
+                "version_value": "1.3.1",
+            },
+            {
+                "version_affected": "<",
+                "version_value": "1.3.2",
+            },
+        ]
+        fixed_version_ranges, affected_version_ranges = self.data_src.to_version_ranges(data)
+
+        # Check fixed packages
+        assert [
+            VersionSpecifier.from_scheme_version_spec_string("maven", ">=1.3.2")
+        ] == fixed_version_ranges
+
+        # Check vulnerable packages
+        assert [
+            VersionSpecifier.from_scheme_version_spec_string("maven", "==1.3.0"),
+            VersionSpecifier.from_scheme_version_spec_string("maven", "==1.3.1"),
+        ] == affected_version_ranges
+
+    def test_to_advisory(self):
+        expected_advisories = [
+            Advisory(
+                summary="A serious problem exists when a client sends a large number of "
+                "headers with the same header name. Apache uses up memory faster than the "
+                "amount of memory required to simply store the received data itself. That "
+                "is, memory use increases faster and faster as more headers are received, "
+                "rather than increasing at a constant rate. This makes a denial of service "
+                "attack based on this method more effective than methods which cause Apache"
+                " to use memory at a constant rate, since the attacker has to send less data.",
+                affected_packages=[
+                    AffectedPackage(
+                        vulnerable_package=PackageURL(
+                            type="apache",
+                            name="httpd",
+                            version="1.3.0",
+                        ),
+                    ),
+                    AffectedPackage(
+                        vulnerable_package=PackageURL(
+                            type="apache",
+                            name="httpd",
+                            version="1.3.1",
+                        ),
+                    ),
+                ],
+                references=[
+                    Reference(
+                        url="https://httpd.apache.org/security/json/CVE-1999-1199.json",
+                        severities=[
+                            VulnerabilitySeverity(
+                                system=scoring_systems["apache_httpd"],
+                                value="important",
+                            ),
+                        ],
+                        reference_id="CVE-1999-1199",
+                    ),
+                ],
+                vulnerability_id="CVE-1999-1199",
+            )
+        ]
+        found_advisories = [self.data_src.to_advisory(self.data)]
+        found_advisories = list(map(Advisory.normalized, found_advisories))
+        expected_advisories = list(map(Advisory.normalized, expected_advisories))
+        assert sorted(found_advisories) == sorted(expected_advisories)