Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. From version 9.8.0 to before version 9.9.1-alpha.5, apps that enable MFA and deny get on the _User class via Class-Level Permissions could expose sensitive user data through the /login and /verifyPassword endpoints. These endpoints re-fetch the user through the access-controlled query pipeline (CLP, protectedFields, auth-adapter sanitizers) before responding. When that re-fetch was denied by the _User get permission, the server fell back to the raw database row, exposing raw authData (including MFA TOTP secrets and recovery codes) and fields hidden by protectedFields (when protectedFieldsOwnerExempt is false). /verifyPassword is the most severe: with only a username and password (no session or MFA token), an attacker who knows a victim's password could retrieve their MFA secret and recovery codes, defeating the second factor. This issue has been patched in version 9.9.1-alpha.5.
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.79 and 9.9.1-alpha.4, the default file upload extension blocklist can be bypassed by appending a trailing dot to a filename whose extension would otherwise be blocked (e.g. poc.svg.). The trailing dot causes the extension parser to extract an empty string, which short-circuits the blocklist check, and the attacker-controlled Content-Type is forwarded to the storage adapter unchanged. Storage adapters that persist and serve the provided Content-Type (such as S3 or GCS) then serve the file with an active type such as image/svg+xml, enabling stored XSS when a victim opens the file URL. The default GridFS adapter is not affected because it sets X-Content-Type-Options: nosniff on responses. This issue has been patched in versions 8.6.79 and 9.9.1-alpha.4.
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. From version 9.8.0 to before version 9.9.1-alpha.3, the routeAllowList server option restricts external client access to a configured list of REST API routes. The check is only enforced as Express middleware against the outer HTTP request URL, so the /batch handler dispatches each sub-request to the internal router without re-running the allow-list check. An external caller whose outer route matches batch can issue batch sub-requests to any REST API route that the operator omitted from the allow-list. Authentication, ACL, CLP, and other inner-route authorization controls still apply — only the operator-configured route firewall is bypassed. This issue has been patched in version 9.9.1-alpha.3.
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.77 and 9.9.1-alpha.1, an unauthenticated attacker who knows a publicly-known Parse Application ID can submit a single HTTP request whose client SDK version field contains adversarial input that triggers polynomial backtracking in a request-header parser. The parsing runs before session authentication and before rate limiting on every /parse/* request, so the request consumes seconds to minutes of synchronous CPU on a Node.js worker before any access control evaluates it. A small number of concurrent requests can saturate a worker; a single large request via the body-field variant can pin a worker for minutes. Production deployments running the default configuration are affected. This issue has been patched in versions 8.6.77 and 9.9.1-alpha.1.
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.78 and 9.9.1-alpha.2, Parse Server's GraphQL endpoint discloses schema metadata to unauthenticated callers through Did you mean ...? suggestions embedded in GraphQL validation-error messages. An unauthenticated caller who knows only the public application id can iteratively send malformed queries to reconstruct class names, field names, argument names, mutation names, and input-object fields. This issue has been patched in versions 8.6.78 and 9.9.1-alpha.2.
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to 8.6.76 and 9.9.0, a race condition in the MFA SMS one-time password (OTP) login path allows two concurrent /login requests carrying the same OTP to both succeed and both receive valid session tokens, breaking the single-use property of the OTP. The vulnerability requires the attacker to already possess the victim's password and intercept the active SMS OTP (e.g. via SIM swap, network mirror, or phishing relay) and to race the legitimate login request, so the practical attack surface is narrow. This vulnerability is fixed in 8.6.76 and 9.9.0.
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to 9.8.0-alpha.7 and 8.6.75, the GET /sessions/me endpoint returns _Session fields that the server operator explicitly configured as protected via the protectedFields server option. Any authenticated user can retrieve their own session's protected fields with a single request. The equivalent GET /sessions and GET /sessions/:objectId endpoints correctly strip protected fields. This vulnerability is fixed in 9.8.0-alpha.7 and 8.6.75.
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to 9.8.0-alpha.6 and 8.6.74, he login endpoint response time differs measurably depending on whether the submitted username or email exists in the database. When a user is not found, the server responds immediately. When a user exists but the password is wrong, a bcrypt comparison runs first, adding significant latency. This timing difference allows an unauthenticated attacker to enumerate valid usernames. This vulnerability is fixed in 9.8.0-alpha.6 and 8.6.74.
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to 8.6.73 and 9.7.1, a file can be uploaded with a filename extension that passes the file extension allowlist (e.g., .txt) but with a Content-Type header that differs from the extension (e.g., text/html). The Content-Type is passed to the storage adapter without consistency validation. Storage adapters that store and serve the provided Content-Type (such as S3 or GCS) serve the file with the mismatched Content-Type. The default GridFS adapter is not affected because it derives Content-Type from the filename at serving time. This vulnerability is fixed in 8.6.73 and 9.7.1.
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.71 and 9.7.1-alpha.1, file downloads via HTTP Range requests bypass the afterFind(Parse.File) trigger and its validators on storage adapters that support streaming (e.g.the default GridFS adapter). This allows access to files that should be protected by afterFind trigger authorization logic or built-in validators such as requireUser. This issue has been patched in versions 8.6.71 and 9.7.1-alpha.1.
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.63 and 9.7.0-alpha.7, the verify password endpoint returns unsanitized authentication data, including MFA TOTP secrets, recovery codes, and OAuth access tokens. An attacker who knows a user's password can extract the MFA secret to generate valid MFA codes, defeating multi-factor authentication protection. This issue has been patched in versions 8.6.63 and 9.7.0-alpha.7.
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.70 and 9.7.0-alpha.18, an authenticated user with find class-level permission can bypass the protectedFields class-level permission setting on LiveQuery subscriptions. By sending a subscription with a $or, $and, or $nor operator value as a plain object with numeric keys and a length property (an "array-like" object) instead of an array, the protected-field guard is bypassed. The subscription event firing acts as a binary oracle, allowing the attacker to infer whether a protected field matches a given test value. This issue has been patched in versions 8.6.70 and 9.7.0-alpha.18.
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.69 and 9.7.0-alpha.14, an authenticated user can bypass the immutability guard on session fields (expiresAt, createdWith) by sending a null value in a PUT request to the session update endpoint. This allows nullifying the session expiry, making the session valid indefinitely and bypassing configured session length policies. This issue has been patched in versions 8.6.69 and 9.7.0-alpha.14.
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.68 and 9.7.0-alpha.12, the GraphQL query complexity validator can be exploited to cause a denial-of-service by sending a crafted query with binary fan-out fragment spreads. A single unauthenticated request can block the Node.js event loop for seconds, denying service to all concurrent users. This only affects deployments that have enabled the requestComplexity.graphQLDepth or requestComplexity.graphQLFields configuration options. This issue has been patched in versions 8.6.68 and 9.7.0-alpha.12.
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.67 and 9.7.0-alpha.11, an attacker can bypass Cloud Function validator access controls by appending "prototype.constructor" to the function name in the URL. When a Cloud Function handler is declared using the function keyword and its validator is a plain object or arrow function, the trigger store traversal resolves the handler through its own prototype chain while the validator store fails to mirror this traversal, causing all access control enforcement to be skipped. This allows unauthenticated callers to invoke Cloud Functions that are meant to be protected by validators such as requireUser, requireMaster, or custom validation logic. This issue has been patched in versions 8.6.67 and 9.7.0-alpha.11.
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.66 and 9.7.0-alpha.10, the GraphQL API endpoint does not respect the allowOrigin server option and unconditionally allows cross-origin requests from any website. This bypasses origin restrictions that operators configure to control which websites can interact with the Parse Server API. The REST API correctly enforces the configured allowOrigin restriction. This issue has been patched in versions 8.6.66 and 9.7.0-alpha.10.
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.65 and 9.7.0-alpha.9, when multiple clients subscribe to the same class via LiveQuery, the event handlers process each subscriber concurrently using shared mutable objects. The sensitive data filter modifies these shared objects in-place, so when one subscriber's filter removes a protected field, subsequent subscribers may receive the already-filtered object. This can cause protected fields and authentication data to leak to clients that should not see them, or cause clients that should see the data to receive an incomplete object. Additionally, when an afterEvent Cloud Code trigger is registered, one subscriber's trigger modifications can leak to other subscribers through the same shared mutable state. Any Parse Server deployment using LiveQuery with protected fields or afterEvent triggers is affected when multiple clients subscribe to the same class. This issue has been patched in versions 8.6.65 and 9.7.0-alpha.9.
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.64 and 9.7.0-alpha.8, an attacker who possesses a valid authentication provider token and a single MFA recovery code or SMS one-time password can create multiple authenticated sessions by sending concurrent login requests via the authData login endpoint. This defeats the single-use guarantee of MFA recovery codes and SMS one-time passwords, allowing session persistence even after the legitimate user revokes detected sessions. This issue has been patched in versions 8.6.64 and 9.7.0-alpha.8.
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.61 and 9.6.0, an authenticated user calling GET /users/me receives unsanitized auth data, including sensitive credentials such as MFA TOTP secrets and recovery codes. The endpoint internally uses master-level authentication for the session query, and the master context leaks through to the user data, bypassing auth adapter sanitization. An attacker who obtains a user's session token can extract MFA secrets to generate valid TOTP codes indefinitely. This issue has been patched in versions 8.6.61 and 9.6.0
CVE-2026-33624 is a TOCTOU race condition vulnerability in parse-community's parse-server affecting versions prior to 8.6.60 and 9.6.0-alpha.54. An attacker with a user's password and a single MFA recovery code can exploit concurrent login requests to reuse the recovery code multiple times, bypassing its intended single-use restriction. Exploitation requires high privileges (user password), a valid recovery code, and the ability to send rapid concurrent requests. This flaw undermines MFA recovery code security but does not allow unauthorized access without credentials. The vulnerability has a low CVSS score (2.