Vulnerability Description
An issue was discovered in Open vSwitch (OvS) 2.7.x through 2.7.6, affecting ofproto_rule_insert__ 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 != RULE_INITIALIZED. This would work for new flows, but for an old flow the rule state is RULE_REMOVED. The assertion failure causes an OvS crash.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Openvswitch | Openvswitch | >= 2.7.0, <= 2.7.6 |
| Redhat | Openstack | 10 |
| Canonical | Ubuntu Linux | 16.04 |
Related Weaknesses (CWE)
References
- https://access.redhat.com/errata/RHSA-2018:3500Third Party Advisory
- https://access.redhat.com/errata/RHSA-2019:0053Third Party Advisory
- https://access.redhat.com/errata/RHSA-2019:0081Third Party Advisory
- https://github.com/openvswitch/ovs/commit/0befd1f3745055c32940f5faf9559be6a14395ExploitPatchThird Party Advisory
- https://usn.ubuntu.com/3873-1/Third Party Advisory
- https://access.redhat.com/errata/RHSA-2018:3500Third Party Advisory
- https://access.redhat.com/errata/RHSA-2019:0053Third Party Advisory
- https://access.redhat.com/errata/RHSA-2019:0081Third Party Advisory
- https://github.com/openvswitch/ovs/commit/0befd1f3745055c32940f5faf9559be6a14395ExploitPatchThird Party Advisory
- https://usn.ubuntu.com/3873-1/Third Party Advisory
FAQ
What is CVE-2018-17205?
CVE-2018-17205 is a vulnerability with a CVSS score of 7.5 (HIGH). An issue was discovered in Open vSwitch (OvS) 2.7.x through 2.7.6, affecting ofproto_rule_insert__ in ofproto/ofproto.c. During bundle commit, flows that are added in a bundle are applied to ofproto i...
How severe is CVE-2018-17205?
CVE-2018-17205 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2018-17205?
Check the references section above for vendor advisories and patch information. Affected products include: Openvswitch Openvswitch, Redhat Openstack, Canonical Ubuntu Linux.