CVE-2018-17205

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 v3.0 7.5 HIGH
CVSS v2.0 5.0 MEDIUM

7.5^/10

CVSS v3.0 : HIGH

Vector : AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

5.0^/10

CVSS v2.0 : MEDIUM

Vector : AV:N/AC:L/Au:N/C:N/I:N/A:P

Exploitability : 10.0 / Impact : 2.9

Access Vector NETWORK

Access Complexity LOW

Authentication NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact PARTIAL

References

Link	Resource
https://github.com/openvswitch/ovs/commit/0befd1f3745055c32940f5faf9559be6a14395e6	Exploit Patch Third Party Advisory
https://access.redhat.com/errata/RHSA-2018:3500	Third Party Advisory
https://access.redhat.com/errata/RHSA-2019:0081	Third Party Advisory
https://access.redhat.com/errata/RHSA-2019:0053	Third Party Advisory
https://usn.ubuntu.com/3873-1/	Third Party Advisory

Advertisement

Configurations

Configuration 1 (hide)

cpe:2.3:a:openvswitch:openvswitch:*:*:*:*:*:*:*:*

Configuration 2 (hide)

OR	cpe:2.3:a:redhat:openstack:13:::::::*
	cpe:2.3:a:redhat:openstack:10:::::::*

Configuration 3 (hide)

OR	cpe:2.3:o:canonical:ubuntu_linux:16.04::::lts:::
	cpe:2.3:o:canonical:ubuntu_linux:18.04::::lts:::

Information

Published : 2018-09-19 09:29

Updated : 2021-08-04 10:14

NVD link : CVE-2018-17205

Mitre link : CVE-2018-17205

JSON object : View

CWE

CWE-617

Reachable Assertion

Advertisement

Products Affected

canonical

ubuntu_linux

openvswitch

openvswitch

redhat

openstack

{"cve": {"data_type": "CVE", "references": {"reference_data": [{"url": "https://github.com/openvswitch/ovs/commit/0befd1f3745055c32940f5faf9559be6a14395e6", "name": "https://github.com/openvswitch/ovs/commit/0befd1f3745055c32940f5faf9559be6a14395e6", "tags": ["Exploit", "Patch", "Third Party Advisory"], "refsource": "MISC"}, {"url": "https://access.redhat.com/errata/RHSA-2018:3500", "name": "RHSA-2018:3500", "tags": ["Third Party Advisory"], "refsource": "REDHAT"}, {"url": "https://access.redhat.com/errata/RHSA-2019:0081", "name": "RHSA-2019:0081", "tags": ["Third Party Advisory"], "refsource": "REDHAT"}, {"url": "https://access.redhat.com/errata/RHSA-2019:0053", "name": "RHSA-2019:0053", "tags": ["Third Party Advisory"], "refsource": "REDHAT"}, {"url": "https://usn.ubuntu.com/3873-1/", "name": "USN-3873-1", "tags": ["Third Party Advisory"], "refsource": "UBUNTU"}]}, "data_format": "MITRE", "description": {"description_data": [{"lang": "en", "value": "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."}]}, "problemtype": {"problemtype_data": [{"description": [{"lang": "en", "value": "CWE-617"}]}]}, "data_version": "4.0", "CVE_data_meta": {"ID": "CVE-2018-17205", "ASSIGNER": "cve@mitre.org"}}, "impact": {"baseMetricV2": {"cvssV2": {"version": "2.0", "baseScore": 5.0, "accessVector": "NETWORK", "vectorString": "AV:N/AC:L/Au:N/C:N/I:N/A:P", "authentication": "NONE", "integrityImpact": "NONE", "accessComplexity": "LOW", "availabilityImpact": "PARTIAL", "confidentialityImpact": "NONE"}, "severity": "MEDIUM", "acInsufInfo": false, "impactScore": 2.9, "obtainAllPrivilege": false, "exploitabilityScore": 10.0, "obtainUserPrivilege": false, "obtainOtherPrivilege": false, "userInteractionRequired": false}, "baseMetricV3": {"cvssV3": {"scope": "UNCHANGED", "version": "3.0", "baseScore": 7.5, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "NONE"}, "impactScore": 3.6, "exploitabilityScore": 3.9}}, "publishedDate": "2018-09-19T16:29Z", "configurations": {"nodes": [{"children": [], "operator": "OR", "cpe_match": [{"cpe23Uri": "cpe:2.3:a:openvswitch:openvswitch:*:*:*:*:*:*:*:*", "cpe_name": [], "vulnerable": true, "versionEndIncluding": "2.7.6", "versionStartIncluding": "2.7.0"}]}, {"children": [], "operator": "OR", "cpe_match": [{"cpe23Uri": "cpe:2.3:a:redhat:openstack:13:*:*:*:*:*:*:*", "cpe_name": [], "vulnerable": true}, {"cpe23Uri": "cpe:2.3:a:redhat:openstack:10:*:*:*:*:*:*:*", "cpe_name": [], "vulnerable": true}]}, {"children": [], "operator": "OR", "cpe_match": [{"cpe23Uri": "cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*", "cpe_name": [], "vulnerable": true}, {"cpe23Uri": "cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*", "cpe_name": [], "vulnerable": true}]}], "CVE_data_version": "4.0"}, "lastModifiedDate": "2021-08-04T17:14Z"}