C/C++ | Snyk User Docs (2024)

Supported frameworks and package managers

Code analysis

Snyk Code supports the following:

• Operating systems

  • Linux

  • Windows (limited)

• Embedded systems: Linux

• GUI Framework

• Libraries: POSIX, C++ Standard Library, Boost, Qt (limited)

Open source and licensing

Open source policy

To manage licenses from your developer workflows through policy, see the following topics:

• Defining a secure open source policy

• Use Snyk security policies to prioritize fixes more efficiently

Open source license compliance

To check compliance for open source licenses, see Getting Started with Snyk License Compliance Management.

Getting started with Snyk for C/C++ across environments

Scans are powered by an open source database, periodically updated with the latest source code from online sources.

When you run the snyk test --unmanaged command, Snyk does the following:

1. Converts all files from your current folder into a list of hashes.

2. Sends hashes to the Snyk scan server to compute the dependencies list.

3. Queries the database to find a list of potentially matching dependencies.

4. Links the dependencies to the known vulnerabilities.

5. Displays the results.

Scanning archives

By default, archives are not scanned. However, Snyk CLI can recursively extract archives to analyze the source code inside.

To enable archive extraction, specify the depth of the extraction using the --max-depth option.

The supported archive formats are:

• zip-like archives

• tar archives

• tar with gzip compression algorithm

Constraints and limitations

Source code dependencies need to be available in the scanned folder

For Snyk CLI to be able to find dependencies in your source code, enough of the full dependencies source code needs to be present in the scanned folder.

Having a large percentage of files in their original (unchanged) form is critical to accurately identifying dependencies and reporting the correct set of vulnerabilities back. Modifying that source code reduces the confidence of the scanning engine, resulting in less accurate results. Other potential issues could include dependencies not being identified or being identified incorrectly, as a different version or even a different package.

The example that follows shows a typical package with dependencies listed:

c-example├── deps│ ├── curl-7.58.0│ │ ├── include│ │ │ ├── Makefile.am│ │ │ ├── Makefile.in│ │ │ ├── README│ │ │ └── curl│ │ ├── install-sh│ │ ├── lib│ │ │ ├── asyn.h│ │ │ ├── base64.c│ │ │ ├── checksrc.pl│ │ │ ├── config-amigaos.h│ │ │ ├── conncache.c│ │ │ ├── conncache.h│ │ ├── src│ │ │ ├── tool_binmode.c│ │ │ ├── tool_binmode.h│ │ │ ├── tool_bname.c│ │ │ ├── tool_xattr.c...

Version identification

Only official releases are tracked. Commits, including into the default branch, are not identified unless included in an official release or tag.

Data collection note

When you scan C++ Projects, the following data is collected and may be stored for troubleshooting purposes:

Hashes of the scanned files: All files are converted to a list of irreversible hashes.

Relative paths to scanned files: The paths to files relative to the directory being scanned are included for better identification and matching.Example:./project-name/vendor/bzip2-1.0.6/blocksort.c

Snyk CLI

Prerequisites

1. Create a Snyk account

2. Install Snyk CLI and authenticate your machine

3. Set the default Organization for all Snyk tests (code analysis)

Code analysis

To start testing your code using Snyk Code open your repository in a terminal and run the following command:

snyk code test

To customize test options, run other commands, exclude directories and files, and explore the results in different formats, see the following:

• Snyk CLI commands

• Exclude directories and files from the Snyk tests

• Explore test results in a JSON or SARIF format in the terminal

• Exporting the test results to a JSON or SARIF file

Open source and licensing

Run the test

To test your Project for vulnerabilities, run the following:

$ snyk test --unmanaged

Displaying dependencies

To display dependencies, use the --print-deps option:

$ snyk test --unmanaged --print-depsTesting /Users/user/src/foo...Dependencies: https://curl.se|curl@7.29.0 purl: pkg:generic/curl@7.29.0?download_url=https:%2F%2Fcurl.se%2Fdownload%2Farcheology%2Fcurl-7.29.0.tar.gz confidence: 1.000 https://github.com|nih-at/libzip@1.8.0 purl: pkg:generic/libzip@1.8.0?download_url=https:%2F%2Fgithub.com%2Fnih-at%2Flibzip%2Farchive%2Fv1.8.0.tar.gz confidence: 1.000 https://github.com|madler/zlib@1.2.11 purl: pkg:generic/zlib@1.2.11?download_url=https:%2F%2Fzlib.net%2Ffossils%2Fzlib-1.2.11.tar.gz confidence: 1.000

To learn what files contributed to each dependency being identified, use the --print-dep-paths option:

$ snyk test --unmanaged --print-dep-pathsTesting /Users/user/src/foo...Dependencies: https://curl.se|curl@7.29.0 purl: pkg:generic/curl@7.29.0?download_url=https:%2F%2Fcurl.se%2Fdownload%2Farcheology%2Fcurl-7.29.0.tar.gz confidence: 1.000 matching files: - curl-7.29.0/Android.mk - curl-7.29.0/CHANGES - curl-7.29.0/CMake/CMakeConfigurableFile.in ... and 1766 more files https://github.com|nih-at/libzip@1.8.0 purl: pkg:generic/libzip@1.8.0?download_url=https:%2F%2Fgithub.com%2Fnih-at%2Flibzip%2Farchive%2Fv1.8.0.tar.gz confidence: 1.000 matching files: - libzip-1.8.0/API-CHANGES.md - libzip-1.8.0/AUTHORS - libzip-1.8.0/CMakeLists.txt ... and 780 more files https://github.com|madler/zlib@1.2.11 purl: pkg:generic/zlib@1.2.11?download_url=https:%2F%2Fzlib.net%2Ffossils%2Fzlib-1.2.11.tar.gz confidence: 1.000 matching files: - zlib-1.2.11/CMakeLists.txt - zlib-1.2.11/ChangeLog - zlib-1.2.11/FAQ ... and 249 more files

Understanding the confidence level

You may need to change the source code of the dependencies that you use in your software. As Snyk uses file signatures to find the closest possible match to an open-source library, your changes may decrease the accuracy of the identification of the actual library.

To learn how confident Snyk is about the identified dependency and its version, use the --print-deps or --print-dep-paths command line option:

curl|https://github.com/curl/curl/releases/download/curl-7_58_0/curl-7.58.0.tar.xz@7.58.0confidence: 0.993

This confidence level shows how confident Snyk is about the actual identification of the dependency. The number can be between 0 and 1 and the higher it is, the more accurate the identification is. Thus a confidence of 1 means that all the files in the source tree fully matched all the expected files in the Snyk database.

JSON output

To get a machine-readable output in JSON, use the --json option:

$ snyk test --unmanaged --json[ { "issues": [ { "pkgName": "curl|https://github.com/curl/curl/releases/download/curl-7_58_0/curl-7.58.0.tar.xz", "pkgVersion": "7.58.0", "issueId": "CVE-2019-5481", "fixInfo": { "isPatchable": false, "isPinnable": false } } ], "issuesData": { "CVE-2019-5481": { "severity": "high", "CVSSv3": "", "originalSeverity": "high", "severityWithCritical": "high", "type": "vuln", "alternativeIds": [ "" ], "creationTime": "2019-09-16T19:15:00.000Z", "disclosureTime": "2019-09-16T19:15:00.000Z", "modificationTime": "2020-10-20T22:15:00.000Z", "publicationTime": "2019-09-16T19:15:00.000Z", "credit": [ "" ], "id": "CVE-2019-5481", "packageManager": "cpp", "packageName": "curl|https://github.com/curl/curl/releases/download/curl-7_58_0/curl-7.58.0.tar.xz", "language": "cpp", "fixedIn": [ "" ], "patches": [], "exploit": "No Data", "functions": [ "" ], "semver": { "vulnerable": [ "7.58.0" ], "vulnerableHashes": [ "" ], "vulnerableByDistro": {} }, "references": [ { "title": "https://curl.haxx.se/docs/CVE-2019-5481.html", "url": "https://curl.haxx.se/docs/CVE-2019-5481.html" }, ], "internal": {}, "identifiers": { "CVE": [ "CVE-2019-5481" ], "CWE": [], "ALTERNATIVE": [ "" ] }, "title": "CVE-2019-5481", "description": "", "license": "", "proprietary": true, "nearestFixedInVersion": "" } }, "fileSignaturesDetails": { "https://curl.se|curl@7.58.0": { "artifact": "curl", "version": "7.58.0", "author": "curl", "path": "curl-7.58.0", "id": "59d80da8ba341aaff828662700000000", "url": "https://curl.se/download/curl-7.58.0.tar.gz", "purl": "pkg:generic/curl@7.58.0?download_url=https:%2F%2Fcurl.se%2Fdownload%2Fcurl-7.58.0.tar.gz", "score": 1, "confidence": 1, "filePaths": [ "deps/curl-7.58.0/CHANGES", "c-example/deps/curl-7.58.0/CMake/CMakeConfigurableFile.in", "c-example/deps/curl-7.58.0/CMake/CurlSymbolHiding.cmake" ], "confidence": 1 } } }]

Command line options

The following snyk command line options are supported with the snyk test --unmanaged and snyk monitor --unmanaged commands:

--org=<ORG_ID>--json--json-file-output=<OUTPUT_FILE_PATH> (snyk test only)--remote-repo-url=<URL>--severity-threshold=<low|medium|high|critical> (snyk test only)--max-depth--print-dep-paths--target-reference=<TARGET_REFERENCE> (snyk monitor only)--project-name=<c-project> (snyk monitor only)

For more information about command line options, see the Snyk help docs: Options for scanning with snyk test --unmanaged or snyk monitor --unmanaged.

To import the test results (issues and dependencies) in the Snyk CLI, run the snyk monitor --unmanaged command:

$ snyk monitor --unmanagedMonitoring /c-example (c-example)...Explore this snapshot at https://app.snyk.io/org/example-org/project/8ac0e233-d0f9-403e-b422-5970e7a37443/history/5de4616d-3967-485f-bf21-bbbe91068029Notifications about newly disclosed issues related to these dependencies will be emailed to you.

This creates a snapshot of dependencies and vulnerabilities and imports them into the Snyk Web UI, where you can review the issues and see them included in your reports.

Importing a Project with unmanaged dependencies creates a new Project:

Snyk integrations

Snyk Code

No additional options are required. The Snyk plugin has views within the IDE for displaying results.

Snyk Open Source

Under Additional Parameters in the IDE settings, enter the --unmanaged option to scan for C/C++ open source dependencies.

Help

🔗 See best practices and troubleshooting.