// For flags

CVE-2018-17204

openvswitch: Mishandle of group mods in lib/ofp-util.c:parse_group_prop_ntr_selection_method() allows for assertion failure

Severity Score

4.3
*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

-
*SSVC
Descriptions

An issue was discovered in Open vSwitch (OvS) 2.7.x through 2.7.6, affecting parse_group_prop_ntr_selection_method in lib/ofp-util.c. When decoding a group mod, it validates the group type and command after the whole group mod has been decoded. The OF1.5 decoder, however, tries to use the type and command earlier, when it might still be invalid. This causes an assertion failure (via OVS_NOT_REACHED). ovs-vswitchd does not enable support for OpenFlow 1.5 by default.

Se ha descubierto un problema en Open vSwitch (OvS) en versiones 2.7.x hasta la 2.7.6 que afecta a parse_group_prop_ntr_selection_method en lib/ofp-util.c. Cuando se descodifica un mod de grupo, valida el tipo de grupo y comando después de que todo el mod de grupo se haya descodificado. Sin embargo, el decodificador OF1.5 intenta utilizar el tipo y comando antes, cuando puede ser todavía no válido. Esto provoca un fallo de aserción (mediante OVS_NOT_REACHED). ovs-vswitchd tiene deshabilitado el soporte para OpenFlow 1.5 por defecto.

An issue was discovered in Open vSwitch (OvS), 2.4.x through 2.4.1, 2.5.x through 2.5.5, 2.6.x through 2.6.3, 2.7.x through 2.7.6, 2.8.x through 2.8.4, and2.9.x through 2.9.2, affecting the parse_group_prop_ntr_selection_method in lib/ofp-util.c. On controllers with the OpenFlow 1.5 decoder enabled, a specially crafted group update can cause an assertion failure, potentially leading to a Denial of Service condition.

*Credits: N/A
CVSS Scores
Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
Low
Attack Vector
Network
Attack Complexity
Low
Privileges Required
High
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
Low
Attack Vector
Network
Attack Complexity
Low
Authentication
Single
Confidentiality
None
Integrity
None
Availability
Partial
* Common Vulnerability Scoring System
SSVC
  • Decision:-
Exploitation
-
Automatable
-
Tech. Impact
-
* Organization's Worst-case Scenario
Timeline
  • 2018-09-19 CVE Reserved
  • 2018-09-19 CVE Published
  • 2024-07-04 EPSS Updated
  • 2024-08-05 CVE Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-20: Improper Input Validation
  • CWE-617: Reachable Assertion
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Openvswitch
Search vendor "Openvswitch"
 Openvswitch
Search vendor "Openvswitch" for product "Openvswitch"
 >= 2.7.0 <= 2.7.6
Search vendor "Openvswitch" for product "Openvswitch" and version " >= 2.7.0 <= 2.7.6"
-
Affected
Redhat
Search vendor "Redhat"
 Openstack
Search vendor "Redhat" for product "Openstack"
 10
Search vendor "Redhat" for product "Openstack" and version "10"
-
Affected
Redhat
Search vendor "Redhat"
 Openstack
Search vendor "Redhat" for product "Openstack"
 13
Search vendor "Redhat" for product "Openstack" and version "13"
-
Affected
Canonical
Search vendor "Canonical"
 Ubuntu Linux
Search vendor "Canonical" for product "Ubuntu Linux"
 16.04
Search vendor "Canonical" for product "Ubuntu Linux" and version "16.04"
lts
Affected
Canonical
Search vendor "Canonical"
 Ubuntu Linux
Search vendor "Canonical" for product "Ubuntu Linux"
 18.04
Search vendor "Canonical" for product "Ubuntu Linux" and version "18.04"
lts
Affected
Debian
Search vendor "Debian"
 Debian Linux
Search vendor "Debian" for product "Debian Linux"
 9.0
Search vendor "Debian" for product "Debian Linux" and version "9.0"
-
Affected