CVE-2020-4038 Reflected XSS in GraphQL Playground

What is CVE-2020-4038?

CVE-2020-4038 is a high-severity cross-site scripting vulnerability in prisma-labs graphql-playground, published on 8 Jun 2020. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

Official description

GraphQL Playground (graphql-playground-html NPM package) before version 1.6.22 have a severe XSS Reflection attack vulnerability. All unsanitized user input passed into renderPlaygroundPage() method could trigger this vulnerability. This has been patched in graphql-playground-html version 1.6.22. Note that some of the associated dependent middleware packages are also affected including but not limited to graphql-playground-middleware-express before version 1.7.16, graphql-playground-middleware-koa before version 1.6.15, graphql-playground-middleware-lambda before version 1.7.17, and graphql-playground-middleware-hapi before 1.6.13.

Weakness: CWE-79

Which versions are affected by CVE-2020-4038?

2 open source packages ship an affected version, including graphql-playground-html. It affects 5 products.

Products include Prisma Graphql-Playground-Html, Prisma Graphql-Playground-Middleware-Express, Prisma Graphql-Playground-Middleware-Hapi, Prisma Graphql-Playground-Middleware-Koa, Prisma Graphql-Playground-Middleware-Lambda.

How do I fix CVE-2020-4038?

Upgrade graphql-playground-html to 1.6.22 or later.

Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.

Is CVE-2020-4038 being exploited?

There is no known exploitation of CVE-2020-4038 in the wild and no public exploit code.

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-4852-vrh7-28rf.