OSV is committed to bringing our users comprehensive, accurate and timely open source vulnerability information. Over the last year, we’ve released a number of new features in pursuit of this goal including:
- OSV-Scanner’s call graph analysis for Go and Rust
- Adding six new ecosystems to the database
- The determineversion API, which expanded access to C/C++ vulnerabilities for OSS-Fuzz projects
Today we are announcing that OSV advisories now include vulnerable commit ranges. Vulnerable commit ranges, along with the previously announced experimental determineversion API, will enable vulnerability management for software with C and C++ dependencies, which has been one of the last gaps in coverage in OSV.dev’s database. Additionally OSV-Scanner is now compatible with C and C++ projects.
Why are vulnerable commit ranges helpful for matching vulnerabilities?
Because the C/C++ ecosystem doesn’t have a centralized package registry, source code identifiers (e.g. Git hashes) are the best way to identify C/C++ libraries. Typically, vulnerabilities are associated with versions, not Git hashes, making C/C++ vulnerability matching difficult. The new commit level vulnerability information will allow users to confidently match their dependencies to known vulnerabilities within the OSV database.
Vulnerable commit ranges provide a granular approach that more closely follows the development process, matching vulnerabilities to a range of upstream commits instead of matching vulnerabilities to a package version. This precise information allows for accurate identification of Git branches cut from known vulnerable commits and leads to more accurate vulnerability information.
How are vulnerable commit ranges included in the OSV database?
We’ve enriched over 30,000 advisories based on the NVD CVE database. We’ve added vulnerable commit ranges to these advisories by using algorithmic analysis to match Git repository tag information to patch information supplied by the NVD CVE entry.
As part of our work in this area, we’ve established working relationships with the NVD via data quality fixes and longer term systematic improvements.
Sample OSV advisory with commit range information.
Finding C/C++ vulnerabilities with vulnerable commit ranges
Matching C/C++ dependencies to known vulnerabilities has been one of the final pieces in the puzzle of a truly comprehensive open source vulnerability database. Most projects with C/C++ dependencies include a copy of those dependencies bundled with the project, either by using submodules or by vendoring dependencies. Whether dependencies are submoduled or vendored, vulnerable commit ranges allow OSV users to match their dependencies to known vulnerabilities.
Submoduled C/C++ dependencies
For example, let’s consider the yuzu project and see if we can find any vulnerabilities in the project dependencies. We’ll be working from commit
43be2bfe332d5537041262eb08037993239eaf5f for this example.
Follow these steps:
- Clone the yuzu project to your local machine using
git clone https://github.com/yuzu-emu/yuzu. It is not necessary to use
git clone –recursive. OSV-Scanner will be able to determine the appropriate Git commits without the recursive flag.
- Checkout the relevant commit using
git -C yuzu checkout 43be2bfe332d5537041262eb08037993239eaf5f
OSV-Scanner returns the following vulnerabilities from the submoduled dependencies:
Fortunately both cpp-httplib and ffmpeg have fixes for these vulnerabilities and yuzu has updated its copies of these dependencies. The yuzu project is no longer vulnerable to CVE-2023-26130 or CVE-2021-28429.
Vendored C/C++ dependencies
Vendored dependencies are included in a project by simply copying the code into the repository. Git commit information is not retained, so we need another way to determine whether a vulnerability is present. In these cases, OSV-Scanner uses the determineversion API to estimate each dependency’s version (and associated commit), and match it to any known vulnerabilities.
When we released the API in July, its use was limited to vulnerabilities found by OSS-Fuzz. Not all C/C++ projects are part of OSS-Fuzz, nor are all vulnerabilities for a given dependency found by OSS-Fuzz, so users may not find all the vulnerabilities associated with their project. With the addition of the commit level vulnerability data from the NVD, this gap has been significantly narrowed. The determineversion API, and the associated OSV-Scanner functionality, can now be used for the majority of vendored C/C++ dependencies.
Let’s consider the OpenCV project, which uses vendored dependencies. Working from commit
e9e6b1e22c1a966a81aca1217b16a51fe7311b3b, OSV-Scanner is able to find a number of vulnerabilities from the vendored dependencies including:
- CVE-2021-29390 from libjpeg
- CVE-2022-3857 from libpng
- CVE-2023-3618 from libtiff
- CVE-2020-11760 from openexr
- OSV-2022-416 from openjpeg
- CVE-2022-3509 from protobuf
Try it yourself!
Do you have a project that uses C/C++ dependencies? We encourage you to try our new vulnerable commit range features by using the latest OSV-Scanner release and let us know about your experience. If you encounter a data issue, please fill out a data quality report. Your contributions, questions, and feedback will help us improve not only the quality of our data, but will ultimately help users identify and fix vulnerabilities in their projects.