{"cve":"CVE-2021-40085","nvd":{"published":"2021-08-31T18:15:08.837","modified":"2026-06-17T04:06:29.600","status":"Modified","description":"An issue was discovered in OpenStack Neutron before 16.4.1, 17.x before 17.2.1, and 18.x before 18.1.1. Authenticated attackers can reconfigure dnsmasq via a crafted extra_dhcp_opts value.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N","score":6.5},"cwes":[],"references":["http://www.openwall.com/lists/oss-security/2021/08/31/2","https://launchpad.net/bugs/1939733","https://lists.debian.org/debian-lts-announce/2021/10/msg00005.html","https://lists.debian.org/debian-lts-announce/2022/05/msg00038.html","https://security.openstack.org/ossa/OSSA-2021-005.html"],"products":["debian:debian_linux","openstack:neutron"],"source":"nvd","synced_at":"2026-10-19T21:21:57.125947417+00:00"},"epss":{"cve":"CVE-2021-40085","score":0.0183,"percentile":0.78871,"date":"2026-11-01"},"kev":null,"osv":[{"id":"GHSA-fh73-gjvg-349c","url":"https://osv.dev/vulnerability/GHSA-fh73-gjvg-349c","summary":"OpenStack Neutron vulnerable to authenticated attackers reconfiguring dnsmasq via crafted extra_dhcp_opts value","modified":"2024-12-07T05:38:25.490395Z","packages":[{"ecosystem":"PyPI","name":"neutron","purl":"pkg:pypi/neutron","ranges":["<16.4.1"],"fixed":["16.4.1"]},{"ecosystem":"PyPI","name":"neutron","purl":"pkg:pypi/neutron","ranges":[">=17.0.0 <17.2.1"],"fixed":["17.2.1"]},{"ecosystem":"PyPI","name":"neutron","purl":"pkg:pypi/neutron","ranges":[">=18.0.0 <18.1.1"],"fixed":["18.1.1"]}]},{"id":"PYSEC-2021-361","url":"https://osv.dev/vulnerability/PYSEC-2021-361","summary":"","modified":"2026-06-10T17:02:23.776282871Z","packages":[{"ecosystem":"PyPI","name":"neutron","purl":"pkg:pypi/neutron","ranges":["<16.4.1",">=17.0.0 <17.2.1",">=18.0.0 <18.1.1"],"fixed":["16.4.1","17.2.1","18.1.1"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}