{"id":"CVE-2026-81529","aliases":["EUVD-2026-67213"],"status":"published","title":"Connection-option injection via unescaped settings in the canonical MongoDB URL builder","description":"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.","severity":{"version":"4.0","score":7.1,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:H/VI:L/VA:N/SC:H/SI:L/SA:N","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00285,"percentile":0.21166,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-88"],"published":"2026-08-27T18:32:31Z","modified":"2026-10-28T02:30:31Z","products":[{"vendor":"mongodb","product":"c# driver"},{"vendor":"mongodb","product":"c\\#_driver"}],"references":[{"url":"https://jira.mongodb.org/browse/CSHARP-6171","tags":["Vendor Advisory","web"]},{"url":"https://www.nuget.org/packages/MongoDB.Driver/3.11.1","tags":["Product","web"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/81xxx/CVE-2026-81529.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-81529","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-81529","title":"Connection-option injection via unescaped settings in the canonical MongoDB URL builder","description":"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.","status":"published","published":"2026-08-27T18:32:31.65Z","modified":"2026-08-28T16:37:37.138Z","cvss":[{"version":"4.0","score":7.1,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:H/VI:L/VA:N/SC:H/SI:L/SA:N","level":"high","assessor":"cna"},{"version":"3.1","score":7.1,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:L/A:N","level":"high","assessor":"cna"}],"cwes":["CWE-88"],"updated_at":"2026-11-02T13:36:29.327819Z"}],"euvd":[{"id":"EUVD-2026-67213","description":"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.","status":"published","published":"2026-08-27T18:32:31Z","modified":"2026-08-28T16:37:37Z","cvss":[{"version":"4.0","score":7.1,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:H/VI:L/VA:N/SC:H/SI:L/SA:N","level":"high"}],"updated_at":"2026-11-02T18:01:23.104802Z"}],"nvd":[{"id":"CVE-2026-81529","description":"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.","status":"published","published":"2026-08-27T20:18:51.48Z","modified":"2026-09-29T19:16:22.15Z","cvss":[{"version":"4.0","score":7.1,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:H/VI:L/VA:N/SC:H/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high","assessor":"secondary"},{"version":"3.1","score":7.1,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:L/A:N","level":"high","assessor":"secondary"}],"cwes":["CWE-88"],"updated_at":"2026-11-02T14:12:42.035353Z"}],"osv":[{"id":"CVE-2026-81529","title":"Connection-option injection via unescaped settings in the canonical MongoDB URL builder","description":"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.","status":"published","published":"2026-08-27T18:32:31.65Z","modified":"2026-10-28T02:30:31.050995522Z","cvss":[{"version":"4.0","score":7.1,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:H/VI:L/VA:N/SC:H/SI:L/SA:N","level":"high"}],"cwes":["CWE-88"],"updated_at":"2026-11-02T15:45:18.131258Z"}]}}