{"id":"CVE-2026-106435","title":"The MongoDB Python Driver's binary accelerator can read outside a buffer when an application decodes malformed BSON containing a truncated regular-expression element without a trailing NUL byte","summary":"The MongoDB Python Driver's binary accelerator can read outside a buffer when an application decodes malformed BSON containing a truncated regular-expression element without a trailing NUL byte. An actor who can supply BSON to the docume…","severity":"medium","cvss":5.1,"cvssVector":"CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","cwe":["CWE-125"],"vendor":"mongodb","product":"python_driver","affected":["python_driver < 4.18.3"],"patched":["python_driver 4.18.3"],"published":"2026-10-08","updated":"2026-10-15","sourceUpdated":"2026-10-15T17:00:36.980","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-106435","references":[{"url":"https://jira.mongodb.org/browse/PYTHON-6110","label":"cna@mongodb.com"},{"url":"https://github.com/mongodb/mongo-python-driver/security/advisories/GHSA-98qm-wvgf-w4cf"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-106435"},{"url":"https://github.com/mongodb/mongo-python-driver/pull/3109"},{"url":"https://github.com/mongodb/mongo-python-driver/commit/bb8d4e195275e75bd94ebeffb53cc747d357fcf4"},{"url":"https://github.com/mongodb/mongo-python-driver/releases/tag/4.18.3"},{"url":"https://github.com/advisories/GHSA-98qm-wvgf-w4cf"},{"url":"https://github.com/mongodb/mongo-python-driver"}],"tags":["nvd","cve.org","ghsa","pip","osv"],"epss":0.00093,"epssPercentile":0.00562,"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-10-09T11:49:15.521416Z"},"ingestedAt":"2026-10-08T22:11:53.856Z","aliases":["GHSA-98qm-wvgf-w4cf"],"ecosystem":"pip","slug":"CVE-2026-106435","body":"## Overview\n\nThe MongoDB Python Driver's binary accelerator can read outside a buffer when an application decodes malformed BSON containing a truncated regular-expression element without a trailing NUL byte. An actor who can supply BSON to the documented decode or decode_all API can cause the application process to terminate when the C extension is loaded. The driver's normal database wire-protocol path does not reach this code.\n\n## Affected\n\n- `python_driver < 4.18.3`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `python_driver 4.18.3`\n\n## Package advisory (CVE-2026-106435)\n\nAffected packages:\n\n- `pymongo >= 3.9.0, <= 4.18.2`\n\nPatched in:\n\n- `pymongo 4.18.3`\n\nSource: https://github.com/advisories/GHSA-98qm-wvgf-w4cf","depth":"sunlit","depthScore":28,"depthScoreParts":{"impact":28.1,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}