{"id":"CVE-2026-96746","aliases":["DEBIAN-CVE-2026-96746","EUVD-2026-86263","GHSA-frjf-h5jg-4v46","UBUNTU-CVE-2026-96746"],"status":"published","title":"Heap buffer overflow via mid-scan command list growth in client topology monitoring","description":"An out-of-bounds write in the connection-monitoring logic of the MongoDB C Driver may allow an unauthenticated party who controls name resolution and the responses of the hosts named in a client's connection string to write beyond the end of a heap buffer. This may cause the application using the driver to terminate unexpectedly.","severity":{"version":"4.0","score":8.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00524,"percentile":0.44938,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-787"],"published":"2026-09-24T15:51:15Z","modified":"2026-10-28T02:30:22Z","fixes":[{"ecosystem":"Debian:14","package":"mongo-c-driver","fixed_in":["2.5.5-1"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Debian:12","package":"mongo-c-driver","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.23.1-1","1.23.1-1+deb12u1","1.23.1-1+deb12u2","1.23.1-1+deb12u3","1.24.1-1","1.24.2-1","1.24.3-1","1.24.4-1","1.25.0-1","1.25.1-1","1.25.2-1","1.25.4-1","1.25.4-1.1~exp1","1.26.0-1","1.26.0-1.1","1.26.0-1.1~exp1","1.26.1-1","1.26.2-1","1.27.0-1","1.27.1-1","1.27.2-1","1.27.3-1","1.27.4-1","1.27.5-1","1.27.6-1","1.28.0-1","1.28.1-1","1.29.0-1","1.29.1-1","1.29.2-1","1.30.0-1","1.30.1-1","1.30.2-1","1.30.3-1","1.30.4-1","2.0.2-1","2.1.0-1","2.1.1-1","2.1.2-1","2.2.0-1","2.2.1-1","2.2.2-1","2.2.3-1","2.2.4-1","2.3.0-1","2.3.1-1","2.3.2-1","2.3.3-1","2.4.0-1","2.5.0-1","2.5.1-1","2.5.2-1","2.5.3-1","2.5.5-1"]},{"source":"osv","ecosystem":"Debian:13","package":"mongo-c-driver","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.30.4-1","1.30.4-1+deb13u1","1.30.4-1+deb13u2","1.30.4-1+deb13u3","2.0.2-1","2.1.0-1","2.1.1-1","2.1.2-1","2.2.0-1","2.2.1-1","2.2.2-1","2.2.3-1","2.2.4-1","2.3.0-1","2.3.1-1","2.3.2-1","2.3.3-1","2.4.0-1","2.5.0-1","2.5.1-1","2.5.2-1","2.5.3-1","2.5.5-1"]},{"source":"osv","ecosystem":"Debian:14","package":"mongo-c-driver","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.5.5-1"}]}],"versions":["1.30.4-1","2.0.2-1","2.1.0-1","2.1.1-1","2.1.2-1","2.2.0-1","2.2.1-1","2.2.2-1","2.2.3-1","2.2.4-1","2.3.0-1","2.3.1-1","2.3.2-1","2.3.3-1","2.4.0-1","2.5.0-1","2.5.1-1","2.5.2-1","2.5.3-1"]},{"source":"osv","ecosystem":"Ubuntu:14.04:LTS","package":"pymongo","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.6-1","2.6.2-1","2.6.3-1","2.6.3-1build1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:16.04:LTS","package":"pymongo","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.0.3-1","3.2-1","3.2-1build1","3.2-1ubuntu0.1~esm1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:18.04:LTS","package":"pymongo","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.4.0-1build2","3.6.1+dfsg1-1","3.6.1+dfsg1-1ubuntu0.1~esm1"]},{"source":"osv","ecosystem":"Ubuntu:20.04:LTS","package":"pymongo","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.7.1-1.1","3.7.1-1.1build1","3.10.1-0ubuntu2","3.10.1-0ubuntu2.1"]},{"source":"osv","ecosystem":"Ubuntu:22.04:LTS","package":"pymongo","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.11.0-1build2","3.11.0-1build3","3.11.0-1build4","3.11.0-1ubuntu0.22.04.1"]},{"source":"osv","ecosystem":"Ubuntu:24.04:LTS","package":"pymongo","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.11.0-1build6","3.11.0-1build7","3.11.0-1build8","3.11.0-1ubuntu0.24.04.1"]},{"source":"osv","ecosystem":"Ubuntu:26.10","package":"pymongo","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.16.0-1build1","4.17.0-1"]},{"source":"osv","ecosystem":"Ubuntu:26.04:LTS","package":"pymongo","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.10.1-6","4.15.3-1","4.15.3-2","4.15.5-1","4.16.0-1","4.16.0-1build1"]}],"products":[{"vendor":"mongodb","product":"c driver"},{"vendor":"mongodb inc.","product":"c driver"}],"references":[{"url":"https://github.com/mongodb/mongo-c-driver/security/advisories/GHSA-frjf-h5jg-4v46","tags":["advisory"]},{"url":"https://github.com/mongodb/mongo-c-driver/releases/tag/1.30.12","tags":["web"]},{"url":"https://github.com/mongodb/mongo-c-driver/releases/tag/2.5.5","tags":["web"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/96xxx/CVE-2026-96746.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-96746","tags":["advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2026-96746","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2026-96746","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-96746","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2026-96746","title":"Heap buffer overflow via mid-scan command list growth in client topology monitoring","description":"An out-of-bounds write in the connection-monitoring logic of the MongoDB C Driver may allow an unauthenticated party who controls name resolution and the responses of the hosts named in a client's connection string to write beyond the end of a heap buffer. This may cause the application using the driver to terminate unexpectedly.","status":"published","published":"2026-09-24T15:51:15.196Z","modified":"2026-09-24T18:18:08.886Z","cvss":[{"version":"4.0","score":8.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N","level":"high","assessor":"cna"},{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H","level":"medium","assessor":"cna"}],"cwes":["CWE-787"],"updated_at":"2026-11-02T14:20:00.511569Z"}],"euvd":[{"id":"EUVD-2026-86263","description":"An out-of-bounds write in the connection-monitoring logic of the MongoDB C Driver may allow an unauthenticated party who controls name resolution and the responses of the hosts named in a client's connection string to write beyond the end of a heap buffer. This may cause the application using the driver to terminate unexpectedly.","status":"published","published":"2026-09-24T15:51:15Z","modified":"2026-09-24T18:18:08Z","cvss":[{"version":"4.0","score":8.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N","level":"high"}],"updated_at":"2026-11-02T17:27:56.686358Z"}],"nvd":[{"id":"CVE-2026-96746","description":"An out-of-bounds write in the connection-monitoring logic of the MongoDB C Driver may allow an unauthenticated party who controls name resolution and the responses of the hosts named in a client's connection string to write beyond the end of a heap buffer. This may cause the application using the driver to terminate unexpectedly.","status":"published","published":"2026-09-24T16:17:27.46Z","modified":"2026-09-24T21:04:40.34Z","cvss":[{"version":"4.0","score":8.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/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","level":"high","assessor":"secondary"},{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H","level":"medium","assessor":"secondary"}],"cwes":["CWE-787"],"updated_at":"2026-11-02T14:12:51.036099Z"}],"osv":[{"id":"CVE-2026-96746","title":"Heap buffer overflow via mid-scan command list growth in client topology monitoring","description":"An out-of-bounds write in the connection-monitoring logic of the MongoDB C Driver may allow an unauthenticated party who controls name resolution and the responses of the hosts named in a client's connection string to write beyond the end of a heap buffer. This may cause the application using the driver to terminate unexpectedly.","status":"published","published":"2026-09-24T15:51:15.196Z","modified":"2026-10-28T02:30:22.790752201Z","cvss":[{"version":"4.0","score":8.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N","level":"high"}],"cwes":["CWE-787"],"updated_at":"2026-11-02T15:45:21.262447Z"},{"id":"DEBIAN-CVE-2026-96746","description":"An out-of-bounds write in the connection-monitoring logic of the MongoDB C Driver may allow an unauthenticated party who controls name resolution and the responses of the hosts named in a client's connection string to write beyond the end of a heap buffer. This may cause the application using the driver to terminate unexpectedly.","status":"published","published":"2026-09-24T16:17:27.46Z","modified":"2026-10-01T10:00:10.322436088Z","cvss":[{"version":"4.0","score":8.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/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","level":"high"}],"updated_at":"2026-11-02T15:46:07.324252Z"},{"id":"UBUNTU-CVE-2026-96746","description":"An out-of-bounds write in the connection-monitoring logic of the MongoDB C Driver may allow an unauthenticated party who controls name resolution and the responses of the hosts named in a client's connection string to write beyond the end of a heap buffer. This may cause the application using the driver to terminate unexpectedly.","status":"published","published":"2026-09-24T16:17:00Z","modified":"2026-10-17T13:01:19.627228598Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H","level":"medium"},{"version":"4.0","score":8.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N","level":"high"}],"updated_at":"2026-11-02T16:57:44.071534Z"}]}}