CVE-2021-41248

What it is

GraphiQL is the reference implementation of this monorepo, GraphQL IDE, an official project under the GraphQL Foundation. All versions of graphiql older than [email protected] are vulnerable to compromised HTTP schema introspection responses or schema prop values with malicious GraphQL type names, exposing a dynamic XSS attack surface that can allow code injection on operation autocomplete. In order for the attack to take place, the user must load a vulnerable schema in graphiql. There are a number of ways that can occur. By default, the schema URL is not attacker-controllable in graphiql or in its suggested implementations or examples, leaving only very complex attack vectors. If a custom implementation of graphiql's fetcher allows the schema URL to be set dynamically, such as a URL query parameter like ?endpoint= in graphql-playground, or a database provided value, then this custom graphiql implementation is vulnerable to phishing attacks, and thus much more readily available, low or no privelege level xss attacks. The URLs could look like any generic looking graphql schema URL. It should be noted that desktop clients such as Altair, Insomnia, Postwoman, do not appear to be impacted by this. This vulnerability does not impact codemirror-graphql, monaco-graphql or other dependents, as it exists in onHasCompletion.ts in graphiql. It does impact all forks of graphiql, and every released version of graphiql.

At a glance

Exploitability

Can be exploited over the network without logging in, but needs a user to act. High risk of data exposure, data tampering.

Exploit odds

1.3% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2021-11-04 21:15 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-06-17 04:08 UTC Last updatedMost recent change to the record

Why it ranks here

• Exploited in the wild: no, CISA does not list it.
• Exploit odds: 1.3% in the next 30 days (EPSS).
• Severity: 7.1 HIGH (CVSS).
• Fix: a patch or advisory is linked.

Details

Published

2021-11-04 21:15 UTC

Last modified

2026-06-17 04:08 UTC

Exploit probability

1.3% · EPSS, next 30 days

Weakness

CWE-79 · Cross-site scripting

Record status

Modified

Affected

• Graphql Graphiql < 1.4.7

Attack profile CVSS 3.1 · 7.1

Attack vector

Network

Complexity

High

Privileges needed

None

User interaction

Required

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

Low

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2021-41248.md and follow it. Check whether this project is affected by CVE-2021-41248. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

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