F-2026-0003·information-disclosure

Reflected request path and query string in API 'Route Not Found' error responses

Fixedpentestblackboxtypescript
TL;DR

When requesting an invalid or non-existent API endpoint, the server returned a JSON error response that reflected the full requested route, including attacker-controlled query string parameters.

Severity
LOW
Impact
LOW
Likelihood
MEDIUM
Method
MManual review
CAT.
Complexity
LOW
Exploitability
MEDIUM
02Section · Description

Description

When an invalid or non-existent API endpoint was requested, the server returned a JSON error response that reflected the full requested route, including attacker-controlled query string parameters.

Example:

Request: GET /api/address/generate?ael64smq30=1 HTTP/2 Host: www.mynth.ai Response: HTTP/2 404 Not Found Content-Type: application/json; charset=utf-8 {"message":"Route GET:/api/address/generate?ael64smq30=1 not found","error":"Not Found","statusCode":404}

While "route not found" responses are expected, reflecting attacker-controlled input (the query string) can introduce downstream risk if these messages are displayed in a UI, logged verbatim, forwarded to monitoring or alerting systems, or rendered in contexts that may interpret special characters.

03Section · Impact

Impact

Low. Risk surfaces if downstream consumers render the reflected content into rich text or fail to escape special characters.

04Section · Recommendation

Recommendation

  • Avoid reflecting full request paths and query strings in error messages returned to clients.
  • If reflection is required for debugging, truncate reflected content to a safe maximum length and ensure proper escaping and normalization of any reflected input.

Novaswap: Confirmed. Zealynx: Fixed.

Status
Fixed
F-2026-0003