Skip to content

Resolve json-schema prototype pollution vulnerability - #15

Merged
eratio08 merged 2 commits into
masterfrom
copilot/fix-json-schema-vulnerability
Jul 16, 2026
Merged

Resolve json-schema prototype pollution vulnerability#15
eratio08 merged 2 commits into
masterfrom
copilot/fix-json-schema-vulnerability

Conversation

Copilot AI commented Jul 16, 2026

Copy link
Copy Markdown

json-schema@0.2.3, pulled transitively through the Jest toolchain, is vulnerable to prototype pollution (CVE-2021-3918). This updates the resolution to the lowest patched release, 0.4.0.

  • Dependency resolution
    • Add a Yarn resolution for json-schema@0.4.0.
    • Regenerate yarn.lock to remove the vulnerable resolved package.
"resolutions": {
  "json-schema": "0.4.0"
}
  • Reachability assessment
    • Dependency path: jest → jsdom → request → http-signature → jsprim → json-schema.
    • No application source references json-schema or schema-validation APIs.
    • The advisory does not identify a specific API; direct API reachability is indeterminate. High confidence this is development-only scanner remediation rather than an active production exposure.
Original prompt

This section details the Dependabot vulnerability alert you should resolve

<alert_title>json-schema is vulnerable to Prototype Pollution</alert_title>
<alert_description>json-schema before version 0.4.0 is vulnerable to Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution').</alert_description>

critical
GHSA-896r-f27r-55mw, CVE-2021-3918
json-schema
npm
<vulnerable_versions>0.2.3</vulnerable_versions>
<patched_version>0.4.0</patched_version>
<manifest_path>yarn.lock</manifest_path>

https://nvd.nist.gov/vuln/detail/CVE-2021-3918 https://github.com/kriszyp/json-schema/commit/22f146111f541d9737e832823699ad3528ca7741 https://huntr.dev/bounties/bb6ccd63-f505-4e3a-b55f-cd2662c261a9 https://github.com/kriszyp/json-schema/commit/b62f1da1ff5442f23443d6be6a92d00e65cba93a https://github.com/kriszyp/json-schema/commit/f6f6a3b02d667aa4ba2d5d50cc19208c4462abfa https://lists.debian.org/debian-lts-announce/2022/12/msg00013.html https://security.netapp.com/advisory/ntap-20250117-0004 https://github.com/advisories/GHSA-896r-f27r-55mw

<task_instructions>Resolve this alert by updating the affected package to a non-vulnerable version. Prefer the lowest non-vulnerable version (see the patched_version field above) over the latest to minimize breaking changes. Include a Reachability Assessment section in the PR description. Review the alert_description field to understand which APIs, features, or configurations are affected, then search the codebase for usage of those specific items. If the vulnerable code path is reachable, explain how (which files, APIs, or call sites use the affected functionality) and note that the codebase is actively exposed to this vulnerability. If the vulnerable code path is not reachable, explain why (e.g. the affected API is never called, the vulnerable configuration is not used) and note that the update is primarily to satisfy vulnerability scanners rather than to address an active risk. If the advisory is too vague to determine reachability (e.g. 'improper input validation' with no specific API named), state that reachability could not be determined and explain why. Include a confidence level in the reachability assessment (e.g. high confidence if the advisory names a specific API and you confirmed it is or is not called, low confidence if the usage is indirect and hard to trace). If no patched version is available, check the alert_description field for a Workarounds section — the advisory may describe configuration changes or usage patterns that mitigate the vulnerability without a version update. If a workaround is available, apply it and leave a code comment referencing the advisory identifier explaining it is a temporary mitigation. If neither a patch nor a workaround is available, explain in the PR description why the alert cannot be resolved automatically so a human reviewer can take over. Inspect the repository to determine which package manager is used (e.g. lock files, config files, build scripts) and use that tooling to perform the update — do not edit lock files directly. If the version constraint in the manifest (e.g. package.json, Gemfile, pyproject.toml) caps the version below the fix, update the constraint first. For transitive dependencies, determine whether it is simpler to update the direct dependency that pulls in the vulnerable package or to update the transitive dependency directly, and choose the least disruptive approach. If upgrading to fix the vulnerability forces a major version bump or known breaking changes, review the changelog or release notes, then audit the codebase for usage of affected APIs and fix any breaking changes that are found. If the package manager fails to resolve dependencies (e.g. peer dependency conflicts, incompatible engine constraints), document the error in the PR description rather than attempting increasingly complex workarounds. After updating, check the lock file to confirm the package no longer resolves to a version in the vulnerable range. Keep changes minimal and tightly scoped. Ensure tests, build, type checking, and linting all pass after your changes. If there are any test, lint, or typechecking failures, investigate whether they are caused by the update and fix them if so — do not leave broken tests in the PR. If they were already present before the update, note them in the PR description so a human reviewer can assess whether they are related.</task_instructions>

Copilot AI changed the title [WIP] Fix critical vulnerability in json-schema package Resolve json-schema prototype pollution vulnerability Jul 16, 2026
Copilot AI requested a review from eratio08 July 16, 2026 06:42
@eratio08
eratio08 marked this pull request as ready for review July 16, 2026 11:30
Copilot AI review requested due to automatic review settings July 16, 2026 11:30
@eratio08
eratio08 merged commit 3e6f09e into master Jul 16, 2026

Copilot AI left a comment

Copy link
Copy Markdown

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Pull request overview

Updates the repository’s Yarn dependency resolution to ensure the transitive json-schema package is resolved to the first patched release (0.4.0) to address CVE-2021-3918 / GHSA-896r-f27r-55mw in the Jest toolchain dependency path.

Changes:

  • Add a Yarn resolutions entry pinning json-schema to 0.4.0.
  • Regenerate yarn.lock so json-schema resolves to 0.4.0 (and the 0.2.3 tarball is no longer present).

Reviewed changes

Copilot reviewed 1 out of 2 changed files in this pull request and generated no comments.

File Description
package.json Adds Yarn resolutions to force json-schema to 0.4.0.
yarn.lock Updates the resolved json-schema entry to 0.4.0 (patched) and removes the old 0.2.3 artifact.

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Labels

None yet

Development

Successfully merging this pull request may close these issues.

3 participants