CVE-2025-29157: Swagger Petstore RCE Vulnerability

CVE-2025-29157 Overview

CVE-2025-29157 affects Smartbear Swagger Petstore version 1.0.7. The application returns a verbose 404 error page when a client requests a non-existent endpoint such as /cart. That error page discloses sensitive server information, including the default servlet name and the underlying server version. A remote, unauthenticated attacker can trigger the response over the network and use the leaked data to fingerprint the deployment and plan follow-on attacks. The vulnerability is classified under [CWE-77] and carries a CVSS 3.1 base score of 6.5.

Critical Impact
Unauthenticated remote attackers can enumerate server internals through default 404 error responses, enabling targeted exploitation of the identified stack.

Affected Products

Smartbear Swagger Petstore 1.0.7
Deployments using the default servlet configuration
Instances exposing the Petstore reference implementation to untrusted networks

Discovery Timeline

2025-09-25 - CVE-2025-29157 published to NVD
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2025-29157

Vulnerability Analysis

The Swagger Petstore reference application ships with a default error handler that renders detailed diagnostic content for unmatched request paths. When an attacker requests an endpoint that is not registered, such as /cart, the server responds with an HTTP 404 page that embeds the servlet identifier and the servlet container version string.

That metadata narrows the attack surface. An attacker who learns the exact server version can cross-reference public vulnerability databases and select exploits that match the fingerprinted stack. The issue does not require authentication or user interaction and is reachable over any network path that can hit the application.

Although the National Vulnerability Database entry references CWE-77 (Command Injection), the documented behavior is information disclosure through error message content. The disclosed values act as a precursor for command injection or remote code execution attempts against the identified components.

Root Cause

The root cause is an insecure default configuration. The Petstore distribution leaves the container's default error page enabled, and that page echoes servlet and server identifiers instead of returning a generic response. No sanitization is applied before the diagnostic strings are written into the HTML body.

Attack Vector

Exploitation requires a single unauthenticated HTTP request to any path that the application does not route, for example GET /cart HTTP/1.1. The response body contains the servlet name default and the server version banner, which the attacker parses to fingerprint the target. See the Swagger Petstore repository and the public proof-of-concept notes for the observed response content.

Detection Methods for CVE-2025-29157

Indicators of Compromise

Repeated HTTP 404 responses from a single source targeting non-existent paths such as /cart, /admin, or /debug.
Outbound 404 response bodies that contain the strings Servlet and a version banner.
User-Agent strings associated with automated scanners hitting Petstore deployments.

Detection Strategies

Inspect web server access logs for high-frequency 404 responses originating from the same IP or ASN.
Deploy a web application firewall rule that flags 404 responses whose body length exceeds a baseline for the application.
Add an application-layer test that requests /cart and alerts if the response body contains Servlet or a version identifier.

Monitoring Recommendations

Forward web server and reverse proxy logs to a central analytics platform and correlate 4xx spikes with reconnaissance patterns.
Alert when the Petstore application returns non-standard error content to external networks.
Track scanner signatures and known exploit-framework User-Agent values against Petstore endpoints.

How to Mitigate CVE-2025-29157

Immediate Actions Required

Restrict access to Swagger Petstore 1.0.7 deployments so they are not reachable from untrusted networks.
Replace the default error page with a generic response that returns only the HTTP status code and no server metadata.
Audit deployed instances for exposure by requesting /cart and reviewing the response body.

Patch Information

No vendor patch is listed in the NVD entry for CVE-2025-29157. Track the Swagger Petstore repository for updates and remove or replace the version 1.0.7 build once a fixed release is available. The Petstore project is a reference implementation, so operators should treat production exposure as a configuration risk.

Workarounds

Configure the servlet container to serve a custom error page for HTTP 404 responses that omits server and servlet identifiers.
Place the application behind a reverse proxy that rewrites error responses and strips the Server header.
Disable directory listings and verbose stack traces in the servlet container configuration.

bash

# Example: define a custom 404 page in web.xml to suppress default error content
# <error-page>
#   <error-code>404</error-code>
#   <location>/WEB-INF/errors/404.html</location>
# </error-page>