CVE-2026-47138
Parse Server: Pre-authentication denial of service via client version header regex backtracking
Description
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.
INFO
Published Date :
June 12, 2026, 7:16 p.m.
Last Modified :
Oct. 26, 2026, 11:10 a.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-47138
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 4.0 | HIGH | [email protected] |
Solution
- Update Parse Server to version 8.6.77 or later.
- Update Parse Server to version 9.9.1-alpha.1 or later.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-47138.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-47138 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-47138
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-47138 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-47138 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Translated by [email protected]
Oct. 26, 2026
Action Type Old Value New Value Added Translation Title: parse-server de parse-community, Description: Parse Server es un backend de código abierto que puede ser desplegado en cualquier infraestructura que pueda ejecutar Node.js. Antes de las versiones 8.6.77 y 9.9.1-alpha.1, un atacante no autenticado que conoce un ID de aplicación de Parse conocido públicamente puede enviar una única solicitud HTTP cuyo campo de versión del SDK del cliente contiene una entrada adversaria que desencadena un retroceso polinómico en un analizador de encabezados de solicitud. El análisis se ejecuta antes de la autenticación de sesión y antes de la limitación de velocidad en cada solicitud /parse/*, por lo que la solicitud consume de segundos a minutos de CPU síncrona en un trabajador de Node.js antes de que cualquier control de acceso lo evalúe. Un pequeño número de solicitudes concurrentes puede saturar un trabajador; una única solicitud grande a través de la variante del campo de cuerpo puede mantener ocupado a un trabajador durante minutos. Las implementaciones en producción que ejecutan la configuración predeterminada se ven afectadas. Este problema ha sido parcheado en las versiones 8.6.77 y 9.9.1-alpha.1. -
CVE Modified by [email protected]
Jun. 17, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'parse-community', 'product': 'parse-server', 'versions': [{'status': 'affected', 'version': '< 8.6.77'}, {'status': 'affected', 'version': '>= 9.0.0, < 9.9.1-alpha.1'}]}] -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 17, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-47138', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-06-12T18:56:09.032234Z'} -
New CVE Received by [email protected]
Jun. 12, 2026
Action Type Old Value New Value Added Description 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. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CWE CWE-1333 Added Reference https://github.com/parse-community/parse-server/pull/10463 Added Reference https://github.com/parse-community/parse-server/pull/10464 Added Reference https://github.com/parse-community/parse-server/security/advisories/GHSA-38m6-82c8-4xfm