Mass Assignment via Onboarding Endpoint Allows Unauthenticated JWT_SECRET Overwrite

Description

Hoppscotch is an API development ecosystem. In self-hosted deployments of hoppscotch-backend from version 2026.4.1 and earlier, the unauthenticated POST /v1/onboarding/config endpoint is vulnerable to mass assignment. The global NestJS ValidationPipe is configured without whitelist: true, so extra properties on the request body that are not declared in SaveOnboardingConfigRequest are not stripped and are iterated in the service layer as if they were legitimate InfraConfig entries. Because keys such as JWT_SECRET and SESSION_SECRET are valid InfraConfigEnum values and are not explicitly rejected during validation, an unauthenticated attacker who can reach a fresh instance before onboarding completes (or when no users exist) can overwrite these values in the database. Overwriting JWT_SECRET gives the attacker control of the JWT signing key, allowing them to forge tokens for any user, including administrators, and results in full server compromise. The issue is fixed in hoppscotch 2026.5.0.

Scores

EPSS (exploitation in 30 days)

1.7% · top 23% of all CVEs (6 Nov 2026)

CISA SSVC

Exploitation: poc · Automatable: yes · Technical impact: total

The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 10.0.

Weakness

• CWE-915: Improperly Controlled Modification of Dynamically-Determined Object Attributes (opens in a new tab)All about CWE-915 and its CVEs

Affected products

• hoppscotch · hoppscotch

  • affected <= 2026.4.1

References (3)

• https://github.com/hoppscotch/hoppscotch/security/advisories/GHSA-j542-4rch-8hwf (opens in a new tab)x_refsource_CONFIRMexploit
• https://github.com/hoppscotch/hoppscotch/pull/6171 (opens in a new tab)x_refsource_MISC
• http://www.openwall.com/lists/oss-security/2026/06/23/7 (opens in a new tab)

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisories (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2026-50160](https://trackcve.app/badge/CVE-2026-50160.svg)](https://trackcve.app/cve/CVE-2026-50160)

Record last updated 2 Jul 2026, 03:57 UTC.