CVE-2018-17205: High severity Openvswitch OpenvSwitch vulnerability
An issue was discovered in Open vSwitch (OvS) 2.7.x through 2.7.6, affecting ofprotoruleinsert in ofproto/ofproto.c. During bundle commit, flows that are added in a bundle are applied to ofproto in order. If a flow cannot be added (e.g., the flow action is a go-to for a group id that does not exist), OvS tries to revert back all previous flows that were successfully applied from the same bundle. This is possible since OvS maintains list of old flows that were replaced by flows from the bundle. While reinserting old flows, OvS has an assertion failure due to a check on rule state != RULEINITIALIZED. This would work for new flows, but for an old flow the rule state is RULEREMOVED. The assertion failure causes an OvS crash.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
debian/openvswitchto a version that resolves this vulnerability.Fixed in 2.15.0+ds1-2+deb11u5Fixed in 3.1.0-2+deb12u1Fixed in 3.5.0-1Fixed in 3.7.1-3
Event History
Frequently Asked Questions
What is CVE-2018-17205?
CVE-2018-17205 is a vulnerability in Open vSwitch (OvS) 2.7.x through 2.7.6 affecting ofproto_rule_insert__ function in ofproto/ofproto.c.
How does CVE-2018-17205 affect Open vSwitch?
CVE-2018-17205 affects Open vSwitch by allowing attackers to add malicious flow actions that can cause denial of service or other impact.
What is the severity of CVE-2018-17205?
The severity of CVE-2018-17205 is high, with a CVSS score of 7.5.
How can I fix CVE-2018-17205?
To fix CVE-2018-17205, update Open vSwitch to version 2.10.7, 2.15.0, 3.1.0, or 3.2.0 for Debian, or version 2.9.2 for Ubuntu 18.04.
Where can I find more information about CVE-2018-17205?
You can find more information about CVE-2018-17205 in the following references: [Red Hat Security Advisory RHSA-2018:3500](https://access.redhat.com/errata/RHSA-2018:3500), [Red Hat Security Advisory RHSA-2019:0053](https://access.redhat.com/errata/RHSA-2019:0053), [Red Hat Security Advisory RHSA-2019:0081](https://access.redhat.com/errata/RHSA-2019:0081).