Hoppscotch is an open source API development ecosystem. Prior to 2026.6.0, the team, teamMembers.user, RESTHistory, GQLHistory, currentRESTSession, currentGQLSession, environments, globalEnvironments, and settings GraphQL paths expose another workspace member's private User data, while toggleHistoryStarStatus and removeRequestFromHistory in the UserHistory service accept another user's history identifier without enforcing userUid ownership, allowing an authenticated workspace member to read private request history, session data, request contents, authorization headers, environment values, and settings and to modify or delete the victim's private history entries. This issue is fixed in version 2026.6.0.

Hoppscotch is an open source API development ecosystem. Prior to 2026.6.0, the updateInfraConfigs GraphQL mutation in admin/infra.resolver.ts accepts an attacker-controlled MAILER_SMTP_URL value, and validateSMTPUrl in utils.ts permits path, query, or fragment content that nodemailer parses into sendmail transport options, allowing an admin to execute arbitrary commands as root in the backend container after restart and mail sending. This issue is fixed in version 2026.6.0.

Hoppscotch is an open source API development ecosystem. Prior to 2026.6.0, mock server creation in mock-server.service.ts does not persist the isPublic input field while schema.prisma defaults isPublic to true, causing mock servers linked to private collections to be publicly accessible without authentication and potentially expose sensitive API data. This issue is fixed in version 2026.6.0.

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.

hoppscotch is an open source API development ecosystem. The fix for CVE-2026-28215 in version 2026.2.0 addresses the unauthenticated POST /v1/onboarding/config endpoint by checking onboardingCompleted and canReRunOnboarding before allowing config overwrites. However, GET /v1/onboarding/config still leaks all infrastructure secrets in plaintext to unauthenticated users when the ONBOARDING_RECOVERY_TOKEN stored in the database is an empty string. This vulnerability is fixed in 2026.4.0.

hoppscotch is an open source API development ecosystem. Prior to version 2026.3.0, there is an open redirect vulnerability that leads to token exfiltration. With these tokens, the attacker can sign in as the victim to takeover their account. This issue has been patched in version 2026.3.0.

hoppscotch is an open source API development ecosystem. Prior to version 2026.3.0, the /enter page contains a DOM-based open redirect vulnerability. The redirect query parameter is directly used to construct a URL and redirect the user without proper validation. This issue has been patched in version 2026.3.0.

hoppscotch is an open source API development ecosystem. Prior to version 2026.3.0, there is a stored XSS vulnerability in the team member overflow tooltip via display name. This issue has been patched in version 2026.3.0.

hoppscotch is an open source API development ecosystem. Prior to version 2026.3.0, there is a stored XSS vulnerability that can lead to CSRF. This issue has been patched in version 2026.3.0.

hoppscotch is an open source API development ecosystem. Prior to version 2026.2.1, the DELETE /v1/access-tokens/revoke endpoint allows any authenticated user to delete any other user's PAT by providing its ID, with no ownership verification. This issue has been patched in version 2026.2.1.