{"id":"CVE-2026-96748","title":"PyMongo's connection string parsing decodes percent-encoded characters in the host portion before the host list is separated on its delimiters","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 conne…","severity":"medium","cvss":6.5,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:N","cwe":["CWE-177","CWE-140"],"vendor":"MongoDB","product":"Python Driver","affected":["python_driver < 4.18.2"],"published":"2026-09-24","updated":"2026-09-24","sourceUpdated":"2026-09-24T21:00:46.893","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-96748","references":[{"url":"https://github.com/mongodb/mongo-python-driver/blob/4.18.2/doc/changelog.rst","label":"cna@mongodb.com"},{"url":"https://github.com/mongodb/mongo-python-driver/releases/tag/4.18.2","label":"cna@mongodb.com"},{"url":"https://github.com/mongodb/mongo-python-driver/security/advisories/GHSA-vp6j-j7w5-5xjj","label":"cna@mongodb.com"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-96748.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-96748"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2540685"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-96748"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-96748"},{"url":"https://github.com/mongodb/mongo-python-driver/pull/3066"},{"url":"https://github.com/mongodb/mongo-python-driver/commit/1e7a56db4649b14c4c9a6ac20aa4a8d0d1bb238a"},{"url":"https://github.com/mongodb/mongo-python-driver/commit/640dd2383a1a2fb1a10e5222d50ebc0b22a61bd7"},{"url":"https://www.mongodb.com/community/forums/t/pymongo-4-18-2-released/343732"},{"url":"https://github.com/advisories/GHSA-vp6j-j7w5-5xjj"},{"url":"https://github.com/mongodb/mongo-python-driver"},{"url":"https://pypi.org/project/pymongo"}],"tags":["nvd","cve.org","csaf","vex","red-hat","ghsa","pip","osv"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-09-24T18:36:30.450714Z"},"ingestedAt":"2026-09-24T18:49:36.719Z","epss":0.00361,"epssPercentile":0.29676,"aliases":["GHSA-vp6j-j7w5-5xjj","PYSEC-2026-4297"],"ecosystem":"pip","patched":["pymongo 4.18.2"],"slug":"CVE-2026-96748","body":"## Overview\n\nPyMongo'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.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Red Hat OpenShift AI (RHOAI), Red Hat OpenStack Platform 13 (Queens), Red Hat OpenStack Platform 16.2, Red Hat OpenStack Platform 17.1 · no fix planned: Red Hat OpenStack Platform 13 (Queens), Red Hat OpenStack Platform 16.2, Red Hat OpenStack Platform 17.1, Red Hat OpenShift AI (RHOAI) · updated 2026-09-29 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-96748.json)\n\n## Package advisory (CVE-2026-96748)\n\nAffected packages:\n\n- `pymongo >= 3.5.0, <= 4.18.1`\n\nPatched in:\n\n- `pymongo 4.18.2`\n\nSource: https://github.com/advisories/GHSA-vp6j-j7w5-5xjj","depth":"sunlit","depthScore":36,"depthScoreParts":{"impact":35.8,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}