Create README.md

README.md

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+---
+license: mit
+language:
+- en
+tags:
+- vulnerabilities
+- vdb
+- sca
+- osv
+- nvd
+- ghsa
+- vers
+- purl
+---
+
+This dataset comprises application and OS vulnerabilities aggregated from multiple sources, including OSV, GitHub, NVD, and Linux vendor feeds, in the form of SQLite data files (.vdb6).
+
+## Vulnerability Data sources
+
+- Linux [vuln-list](https://github.com/appthreat/vuln-list) (Forked from AquaSecurity)
+- OSV (1)
+- NVD
+- GitHub
+
+1 - We exclude Linux and oss-fuzz feeds by default. Set the environment variable `OSV_INCLUDE_FUZZ=true` to include them.
+2 - Malware feeds are included by default, thus increasing the db size slightly. Set the environment variable `OSV_EXCLUDE_MALWARE=true` to exclude them.
+
+## Linux distros
+
+- AlmaLinux
+- Debian
+- Alpine
+- Amazon Linux
+- Arch Linux
+- RHEL/CentOS
+- Rocky Linux
+- Ubuntu
+- OpenSUSE
+- Photon
+- Chainguard
+- Wolfi OS
+
+## Database files
+
+The vulnerability database comprises two SQLite database files.
+
+- data.index.vdb6 - A smaller index database optimized for quick purl or cpe string searches and vers-based range comparisons.
+
+![Index schema](./docs/vdb-index-schema.png)
+
+- data.vdb6 - Full CVE source database containing normalized data in CVE 5.1 specification formation and purl prefix.
+
+![Data schema](./docs/vdb-schema.png)
+
+## Folders
+
+ - app - Application only vulnerabilities from 2018
+ - app-10y - Application only vulnerabilities from 2014
+ - app-os - Application and OS vulnerabilities from 2018
+ - app-os-10y - Application and OS vulnerabilities from 2014
+
+Download data.vdb6 and data.index.vdb6 files from a single folder of your choice.
+
+## Searching for CVEs
+
+Use the smaller index database for all search operations.
+
+### Searching by purl
+
+Given a purl string (`purl_str`), perform the following steps to convert this into a suitable purl prefix (`purl_prefix`) string:
+
+In most cases, a purl prefix is a substring at index 0 after a split by "@". Eg: `purl_prefix = purl_str.split("@")[0]`.
+
+A more robust approach:
+
+- Parse and validate the string using a suitable [library](https://github.com/package-url/). Retain the parsed purl object (`purl_obj`)
+- Construct a purl prefix string with the following logic:
+  - Set the value for `purl_prefix` to `"pkg:" + purl_obj["type"]`
+  - If there is a namespace, append it to purl_prefix after the slash character. Eg: `purl_prefix = purl_prefix + "/" + purl_obj['namespace']`
+  - Optional for Linux distros: If there is a qualifier string with the name `distro_name`, append it to the purl_prefix after the slash character. Eg: `purl_prefix = purl_prefix + "/" + purl_obj['qualifiers']['distro_name']`
+  - Append the name after the slash character. Eg: `purl_prefix = purl_prefix + "/" + purl_obj['name']`
+
+Use the below SQL query to search by purl_prefix:
+
+```
+SELECT DISTINCT cve_id, type, namespace, name, vers, purl_prefix FROM cve_index where purl_prefix = ?;
+```
+
+### Searching by cpe
+
+Parse the cpe string to extract the vendor, product, and version. The regex for python is shown below:
+
+```python
+import re
+
+CPE_FULL_REGEX = re.compile(
+    "cpe:?:[^:]+:(?P<cve_type>[^:]+):(?P<vendor>[^:]+):(?P<package>[^:]+):(?P<version>[^:]+):(?P<update>[^:]+):(?P<edition>[^:]+):(?P<lang>[^:]+):(?P<sw_edition>[^:]+):(?P<target_sw>[^:]+):(?P<target_hw>[^:]+):(?P<other>[^:]+)"
+)
+```
+
+In the `cve_index` table, vendor maps to namespace and package maps to name. The SQL query is below:
+
+```sql
+SELECT DISTINCT cve_id, type, namespace, name, vers, purl_prefix FROM cve_index where namespace = ? AND name = ?;
+```
+
+### Comparing version ranges using vers
+
+Refer to the vers [documentation](https://github.com/package-url/purl-spec/blob/version-range-spec/VERSION-RANGE-SPEC.rst) for information regarding vers and a logic to parse and check if a version is within a range. To simplify the logic, a value from the vers column in `cve_index` would contain only a maximum of two constraints (one greater than and one lesser than).
+
+## Combining data
+
+Search the `cve_index` table in the index database first to retrieve any matching cve_id and purl_prefix values. Use these two column values to retrieve the full CVE source information from the `cve_data` table. An example query is shown below:
+
+```sql
+SELECT DISTINCT cve_id, type, namespace, name, source_data_hash, json(source_data), json(override_data), purl_prefix FROM cve_data
+    WHERE cve_id = ? AND purl_prefix = ?
+    GROUP BY purl_prefix
+    ORDER BY cve_id DESC;
+```
+
+Use the `source_data_hash` values to filter out any duplicate results for the same CVE. Duplicate results are possible when multiple vers match the same CVE and purl prefixes.
+
+## Citation
+
+Use the below citation in your research.
+
+```text
+@misc{vdb,
+  author = {Team AppThreat},
+  month = Feb,
+  title = {{AppThreat vulnerability-db}},
+  howpublished = {{https://huggingface.co/datasets/AppThreat/vdb}},
+  year = {2025}
+}
+```