CVE-2026-96748 (GCVE-0-2026-96748)

Vulnerability from cvelistv5 – Published: 2026-09-24 18:18 – Updated: 2026-09-24 19:12
VLAI
Title
Connection redirection via percent-encoded delimiter injection in connection string hosts
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.
Severity
8.3 (High)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N
6.5 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-24 18:36 UTC
CWE
  • CWE-177 - Improper Handling of URL Encoding (Hex Encoding)
Assigner
mongodb CNA under the mitre root
CNA scorecard C 70/100 over 262 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
MongoDB Python Driver Affected: 0 , < 4.18.2 (semver)
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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