{"id":"DEBIAN-CVE-2026-6691","details":"The MongoDB C Driver's Cyrus SASL integration performs unsafe string copying during username canonicalization, enabling a heap buffer overflow before any authentication or network traffic. This may be triggered by passing untrusted input in the username of a MongoDB URI with authMechanism=GSSAPI.","modified":"2026-09-14T17:03:22.614283393Z","published":"2026-05-06T16:16:11.483Z","upstream":["CVE-2026-6691"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2026-6691"}],"affected":[{"package":{"name":"mongo-c-driver","ecosystem":"Debian:12","purl":"pkg:deb/debian/mongo-c-driver?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.23.1-1+deb12u3"}]}],"versions":["1.23.1-1","1.23.1-1+deb12u1","1.23.1-1+deb12u2"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-6691.json"}},{"package":{"name":"mongo-c-driver","ecosystem":"Debian:13","purl":"pkg:deb/debian/mongo-c-driver?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.30.4-1+deb13u2"}]}],"versions":["1.30.4-1","1.30.4-1+deb13u1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-6691.json"}},{"package":{"name":"mongo-c-driver","ecosystem":"Debian:14","purl":"pkg:deb/debian/mongo-c-driver?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.2.0-1"}]}],"versions":["1.30.4-1","2.0.2-1","2.1.0-1","2.1.1-1","2.1.2-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-6691.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/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"}]}