USN-3586-1: DHCP vulnerabilities
Severity
Medium
Vendor
Canonical Ubuntu
Versions Affected
- Canonical Ubuntu 14.04
Description
Konstantin Orekhov discovered that the DHCP server incorrectly handled a large number of concurrent TCP sessions. A remote attacker could possibly use this issue to cause a denial of service. This issue only affected Ubuntu 14.04 LTS and Ubuntu 16.04 LTS. (CVE-2016-2774)
It was discovered that the DHCP server incorrectly handled socket descriptors. A remote attacker could possibly use this issue to cause a denial of service. (CVE-2017-3144)
Felix Wilhelm discovered that the DHCP client incorrectly handled certain malformed responses. A remote attacker could use this issue to cause the DHCP client to crash, resulting in a denial of service, or possibly execute arbitrary code. In the default installation, attackers would be isolated by the dhclient AppArmor profile. (CVE-2018-5732)
Felix Wilhelm discovered that the DHCP server incorrectly handled reference counting. A remote attacker could possibly use this issue to cause the DHCP server to crash, resulting in a denial of service. (CVE-2018-5733)
Affected Cloud Foundry Products and Versions
Severity is medium unless otherwise noted.
- Cloud Foundry BOSH stemcells are vulnerable, including:
- 3363.x versions prior to 3363.51
- 3421.x versions prior to 3421.43
- 3445.x versions prior to 3445.29
- 3468.x versions prior to 3468.26
- 3541.x versions prior to 3541.8
- All other stemcells not listed.
- All versions of Cloud Foundry cflinuxfs2 prior to 1.189.0
Mitigation
OSS users are strongly encouraged to follow one of the mitigations below:
- The Cloud Foundry project recommends upgrading the following BOSH stemcells:
- Upgrade 3363.x versions to 3363.51
- Upgrade 3421.x versions to 3421.43
- Upgrade 3445.x versions to 3445.29
- Upgrade 3468.x versions to 3468.26
- Upgrade 3541.x versions to 3541.8
- All other stemcells should be upgraded to the latest version available on bosh.io.
- The Cloud Foundry project recommends that Cloud Foundry deployments run with cflinuxfs2 version 1.189.0 or later.
