CVE-2020-4038 | Reflected XSS in GraphQL Playground

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.

Published: 2020-06-08 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2020-4038 is rated Moderate Risk (57.3/100): CVSS High severity, with high exploitation likelihood (EPSS 7.24%, 94th percentile). EPSS ranks this CVE among the most likely to be exploited in the near term. High exploitation likelihood—assess exposure and prioritize remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2020-4038

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 33.49% 7.24% -26.24%
2 2026-03-04 28.57% 33.49% +4.92%
3 2026-03-01 — 28.57% —

Full EPSS history (43 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-4038

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.4 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:H/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
 2.8 4.0 [email protected]
7.4 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:H/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
 2.8 4.0 [email protected]
4.3 2.0 MEDIUM
AV:N/AC:M/Au:N/C:N/I:P/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:N)
No availability impact.
 8.6 2.9 [email protected]

Weakness enumeration for CVE-2020-4038

GitHub Security Advisory for CVE-2020-4038

GHSA-4852-vrh7-28rf · Severity: high · Ecosystem: npm — Reflected XSS in GraphQL Playground

Affected software / configurations for CVE-2020-4038

Vendor Product Version Raw CPE
prisma graphql-playground-html < 1.6.22 cpe:2.3:a:prisma:graphql-playground-html:*:*:*:*:*:node.js:*:*
prisma graphql-playground-middleware-express < 1.7.16 cpe:2.3:a:prisma:graphql-playground-middleware-express:*:*:*:*:*:node.js:*:*
prisma graphql-playground-middleware-hapi < 1.6.13 cpe:2.3:a:prisma:graphql-playground-middleware-hapi:*:*:*:*:*:node.js:*:*
prisma graphql-playground-middleware-koa < 1.6.15 cpe:2.3:a:prisma:graphql-playground-middleware-koa:*:*:*:*:*:node.js:*:*
prisma graphql-playground-middleware-lambda < 1.7.17 cpe:2.3:a:prisma:graphql-playground-middleware-lambda:*:*:*:*:*:node.js:*:*

References for CVE-2020-4038

cvelogic Threat Intelligence