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CVE-2026-96748GHSA-VP6J-J7W5-5XJJPYSEC-2026-4297

Connection redirection via percent-encoded delimiter injection in connection string hosts

Published
Last modified
published
Not listed in CISA KEV
Fix
Fixed in 4.18.2
None on Exploit-DB, Metasploit or GitHub
  • Exploitation: none
  • Automatable: no
  • Technical impact: partial

Summary

PyMongo's connection string parsing decodes percent-encoded characters in the host portion before the host list is separated on its delimiters. When an application places a hostname value supplied by an unauthenticated party into a connection string, that party may cause additional servers of their choosing to be added to the application's database client. The application may then send its authentication exchange and database operations to one of those servers, which can observe limited information and return altered results.

Timeline

  1. CVE published
  2. CISA SSVC assessment

    Exploitation: none · Automatable: no · Technical impact: partial

  3. Record last updated

Affected versions

  • MongoDB Python Driver

    fixed in 4.18.2

  • pymongoPyPI

    From 3.5.0 · fixed in 4.18.2

References 3

GitHub · mongodb/mongo-python-driver