CVE-2026-96748

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.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/mongodb/mongo-python-driver/blob/4.18.2/doc/changelog.rst
https://github.com/mongodb/mongo-python-driver/releases/tag/4.18.2
https://github.com/mongodb/mongo-python-driver/security/advisories/GHSA-vp6j-j7w5-5xjj

Configurations

No configuration.

History

24 Sep 2026, 20:17

Type	Values Removed	Values Added
References		() https://github.com/mongodb/mongo-python-driver/security/advisories/GHSA-vp6j-j7w5-5xjj -

24 Sep 2026, 19:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-24 19:17

Updated : 2026-09-24 21:00

NVD link : CVE-2026-96748

Mitre link : CVE-2026-96748

CVE.ORG link : CVE-2026-96748

JSON object : View

Products Affected

No product.

CWE

CWE-177

Improper Handling of URL Encoding (Hex Encoding)

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