Handling Go Vulnerability Reports

This document explains how we handle vulnerability issue triage in the x/vulndb issue tracker.

Other useful docs:

Reports

All vulnerabilities in the Go vulnerability database are currently stored as a YAML file in the data/reports or data/excluded directory.

For a detailed explanation of the report format and style guide, see doc/format.md.

Issue types

There are 4 types of issues on our tracker:

  1. CVEs/GHSAs created automatically by the worker
  2. Direct external reports from community members
  3. Suggested edits from community members
  4. Placeholder issues for first-party reports

The vast majority of issues are of the first type, and this document focuses on handling these.

Issue states

Any open issue should be in one of the following states:

  • new (no label)
  • triaged
    • standard priority (no additional label)
    • high priority
    • duplicate
    • possibly not Go
  • excluded
  • needs-review
  • out of scope

Maintainers of the Go vulndb move issues from one state to another. The intent behind these explicit states is to describe the (minimum) next steps required to bring the issue to resolution.

new (untriaged)

The issue has been filed by the vulndb worker or an external reporter.

The issue will have the title: x/vulndb: potential Go vuln in <module/package>: <CVE ID and or GHSA ID>.

Use the vulnreport triage command to triage the issue.

triaged

Label: triaged

The issue has been auto-triaged.

The states are:

  • high priority: the issue needs a REVIEWED report
  • standard priority (no label): the issue needs an UNREVIEWED report
  • duplicate: we need to double-check if the issue is a duplicate
  • possibly not Go: we need to check if the issue does not affect Go code

excluded

Label: excluded: REASON where REASON is one of the possible excluded reasons.

The issue represents a reported vulnerability, but is not in scope for the main data/reports folder. An “excluded” report needs to be added to data/excluded.

NOTE: Some excluded reasons are being phased out. The only ones that should be used for new reports are NOT_GO_CODE, NOT_A_VULNERABILITY and DEPENDENT_VULNERABILITY.

NOT_A_VULNERABILITY and DEPENDENT_VULNERABILITY are OK to assign if they obviously apply to a vulnerability, but it is also OK to simply create an unreviewed report if you are not sure.

These can be created using the vulnreport create-excluded command.

needs-review

Label: needs-review

The issue already has an UNREVIEWED report but it should be REVIEWED using the vulnreport review command.

out-of-scope

Label: excluded: OUT_OF_SCOPE or duplicate.

The issue is out of scope for both the data/reports and data/excluded folders. For example, it is an issue mistakenly posted to the tracker (excluded: OUT_OF_SCOPE) or a duplicate (duplicate) of another issue.

The issue can be closed without further action.

Adding new reports

One-time setup

  1. Clone the x/vulndb repository: git clone https://go.googlesource.com/vulndb.

  2. Get a GitHub access token with scope repo: public_repo (follow instructions for “personal access token (classic)”).

    Store the token in a file, e.g., ~/.github-token, and run: export VULN_GITHUB_ACCESS_TOKEN=`cat ~/.github-token` (you can also store this command in a ~/.bashrc file or similar).

  3. (To use experimental generative AI features) Get a Gemini API key.

    As above, you can store the token in a file like ~/.gemini-api-key and use the environment variable GEMINI_API_KEY.

  4. From the repo root, run go install ./cmd/vulnreport to install the latest version of vulnreport tool.

Add a new standard report (label triaged)

  1. Sync your git repo, re-install the vulnreport tool, and create a fresh branch.

  2. From the repo root, run vulnreport create <GitHub issue number>. The vulnreport tool will create a YAML report template for the CVE or GHSA at the specified GitHub issue number.

    Tips for the vulnreport create command:

    • This command works for both regular (reviewed and unreviewed) reports and excluded reports, with no flags or configuration needed.
    • The command accepts multiple Github issue numbers (space separated), and Github issue ranges (e.g., vulnreport create 99 1000-1010 would create reports for issue #99 and all issues from #1000 to #1010, skipping any that are closed, do not exist, or already have reports.)
    • Use the -ai flag to automatically populate a (first-draft) AI-generated summary and description. (See Experimental Features).
    • Use the -symbols flag to attempt to automatically populate vulnerable symbols. (See Experimental Features).
    • By default, the create command attempts to find a GHSA for the vulnerability and pull it from osv.dev. If this is not working, use the -cve flag to use the CVE (rather than the GHSA) as the default source.

  3. Edit the report file template, following the guidance in doc/format.md. A few tips:

    • If a person or organization is given credit in the CVE or GHSA, add the name(s) to the credits field. Otherwise, delete the field.
    • In the vulnerable_at field, put the highest version just before the vuln is fixed. The pkgsite versions page can help with the list of versions. The GitHub UI also makes it easy to list tags (click “Code”, then the dropdown that shows the current branch, then “Tags”). Walk the versions backwards from the fixed one to find the highest that doesn't contain the fix. (It might not be the immediately preceding version.)
    • If the vulnerable functions cannot be auto-populated, add vulnerable functions to the symbols list by reading the CVE, the fixing CLs, and the code at the vulnerable version you chose above.

  4. From the repo root, run vulnreport fix <GitHub issue number>. This will lint the report, add exported symbols, and convert the YAML to OSV.

  5. Once any errors are fixed, run vulnreport commit <GitHub issue number>. This will create a git commit containing the new files with a standard commit message. Commits are to the local git repository. The vulnreport commit command also accepts multiple space-separated issue numbers, and will create a separate commit for each report.

  6. Send the commit for review and approval. See the Go contribution guide for sending a change on Gerrit.

  7. If you make changes to the report during review, re-run vulnreport fix <GitHub issue number> before re-mailing to update the OSV and make sure the report is still valid.

Add a new not-Go-code report (label possibly not Go)

  1. Remove the possibly not Go label
  2. Check if the issue affects Go code
  3. If not
    • Add excluded: NOT_GO_CODE label
    • Add excluded report (see next section)
  4. If yes
    • Create a new standard report (see previous section)

Batch add excluded reports (label excluded: REASON)

  1. Sync your git repo, re-install the vulnreport tool, and create a fresh branch.
  2. Run vulnreport create-excluded. This will batch create YAML reports for all issues with the excluded: REASON label. If there is an error creating any given report, the skipped issue number will be printed to stdout and that issue will have to be created manually with vulnreport create <Github issue number>. (see steps 2-4 above for more information). Additionally, create-excluded will automatically create a single commit for all successful reports. To skip this auto-commit step, use the -dry flag.
  3. Send the commit for review and approval. See the Go contribution guide for sending a change on Gerrit.

Handling duplicates

Sometimes an issue describes a vulnerability that we already have a report for. The worker doesn't always detect this automatically.

If the issue is indeed a duplicate:

  1. Apply the label duplicate to the issue.
  2. Find the duplicate issue (say it is #NNN) in the issue tracker, and on the current issue, write the comment “Duplicate of #NNN”. (No period after the number.)
  3. If a report has already been created for #NNN:
    1. Find the report yaml file (say GO-YYYY-NNNN.yaml) in data/reports, and add the duplicate IDs to the cves or ghsas section, as appropriate. Running vulnreport fix can sometimes find the IDs automatically. (If the duplicate IDs are already present, close the GH issue.)
    2. On a new branch, run vulnreport -up commit NNN to update generated files and create a commit. Edit the generated commit message so that it includes the words “add aliases”. You can also add “Fixes #DDDD” (the number of the duplicate issue) to the commit message, or close it manually.
    3. Mail the commit.
  4. If no report has been created for #NNN yet, make sure the duplicate ID is present somewhere in issue #NNN for reference, and close the duplicate issue.

Standard Library Reports

When adding a vulnerability report about the standard library, ensure that the references section follows this format:

references:
- report: https://go.dev/issue/<#>
- fix: https://go.dev/cl/<#>
- web: https://groups.google.com/g/golang-announce/c/<XXX>/<YYY>

You can find these links in the golang-announce@ email for the security release fixing this vulnerability.

Report: The Github issue will be listed in the golang-announce@ email.

Fix: The PR will be a go.dev/cl/<#> link, found as a gopherbot comment on the issue for the vulnerability.

Web: The golang-announce email link.

Updating a report

Occasionally, we will receive new information about a Go vulnerability and want to update the existing report.

In that case, reopen the issue for the report to discuss the change, rather than create a new issue.

The command vulnreport -up commit NNN can be used to create a more sensible commit message when committing an updated report.

Experimental features

AI-generated summary and description

The command vulnreport suggest <Github issue number> uses Gemini to create AI-generated summaries and descriptions for a report. The -i (interactive) flag gives the option of applying the suggestions directly to the YAML file.

Automatic symbol population

The command vulnreport symbols <Github issue number> uses the commit link(s) in the report to find a list of possibly vulnerable functions (functions that were present in the parent commit and were changed by the patch). Currently, this command cannot handle pull requests or commits with multiple parents.

Frequent issues during triage

This section describes frequent issues that come up when triaging vulndb reports.

vulnreport cgo failures

When vulnreport fix fails with an error message like

/path/to/package@v1.2.3/foo.go:1:2: could not import C (no metadata for C)

a frequent cause is the local machine missing C library headers causing typechecking of cgo packages to fail. The easiest workaround is to use a machine with the development headers installed or to install them.

Commonly missing packages include:

  • libgpgme-dev
  • libdevmapper-dev

“awaiting analysis”

When the NIST page says “AWAITING ANALYSIS”, write the report; don‘t wait for them to finish their analysis. “Awaiting analysis” just means that NVD hasn’t yet looked at the vulnerability and assigned a severity score/CWE etc. Since we don't care about those pieces of information, we can ignore that banner and just create a report if the vulnerability is in scope for our database.