CVE-2026-81529

Improper neutralization of delimiters in connection-URL construction allows connection-option injection in the MongoDB C# Driver. When an application passes untrusted text into the driver's connection-URL builder and round-trips the builder back into a client configuration, the untrusted text is serialized without neutralizing the URL/option delimiters and is then re-parsed as authoritative connection options. A low-privileged user of such an application can thereby introduce or suppress security-relevant connection settings.

  • Published Aug 27, 2026
  • CVSS 7.1 high
  • 0.3% chance of exploitation in the next 30 days (EPSS)

Affected software

CVE-2026-81529 at the National Vulnerability Database