Medium severity · published Aug 31, 2021
CVE-2021-40085
An issue was discovered in OpenStack Neutron before 16.4.1, 17.x before 17.2.1, and 18.x before 18.1.1
6.5
CVSS
1.8%
EPSS
No
On KEV
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 vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.8% · higher than 79% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
9.0; 10.0; 11.0 · source: NVD
NE
Neutron · Openstack
before 16.4.1; 17.0.0 before 17.2.1; 18.0.0 before 18.1.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-40085
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-40085
Mailing List
http://www.openwall.com/lists/oss-security/2021/08/31/2
Exploit
https://launchpad.net/bugs/1939733
Mailing List
https://lists.debian.org/debian-lts-announce/2021/10/msg00005.html
Mailing List
https://lists.debian.org/debian-lts-announce/2022/05/msg00038.html
Patch
https://security.openstack.org/ossa/OSSA-2021-005.html
Third Party Advisory
https://www.debian.org/security/2021/dsa-4983
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