// For flags

CVE-2018-17205

openvswitch: Error during bundle commit in ofproto/ofproto.c:ofproto_rule_insert__() allows for crash

Severity Score

7.5
*CVSS v3

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

1
*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 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.

Se ha descubierto un problema en Open vSwitch (OvS) en versiones 2.7.x hasta la 2.7.6 que afecta a ofproto_rule_insert__ en ofproto/ofproto.c. Durante el commit bundle, los flujos que se añaden a un bundle se aplican a ofproto en orden. Si un flujo no se puede añadir (por ejemplo, la acción flow es un go-to para un ID de grupo que no existe), OvS intenta revertir todos los flujos anteriores cuando se aplican con éxito desde el mismo bundle. Esto es posible porque OvS mantiene una lista de flujos antiguos que se reemplazaron por flujos del bundle. Cuando se vuelve a insertar flujos antiguos, OvS tiene un fallo de aserción debido a una comprobación en la declaración de regla != RULE_INITIALIZED. Esto funcionaría para los nuevos flujos, pero para un flujo antiguo, la sentencia es RULE_REMOVED. El fallo de aserción provoca el cierre inesperado de OvS.

An issue was discovered in Open vSwitch (OvS), 2.7.x through 2.7.6, 2.8.x through 2.8.4, and 2.9.x through 2.9.2, where the ofproto_rule_insert__() function inside ofproto/ofproto.c is affected by an assertion failure under certain circumstances.
A specially crafted flow update applied using the bundling feature of Open vSwitch could potentially cause the assertion failure, potentially leading to incorrect flow information being applied, or a denial of service.

*Credits: N/A
CVSS Scores
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Attack Vector
Network
Attack Complexity
High
Privileges Required
High
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Attack Vector
Network
Attack Complexity
Low
Authentication
None
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
  • 2024-08-05 First Exploit
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
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