CVE-2026-36499
Description
A flaw was found in Open vSwitch. A missing upper-bound check in udpif_set_threads() allows an attacker with OVSDB write access to request an excessive number of handler or revalidation threads, causing resource exhaustion and denial of service. Reported against Open vSwitch v3.6.90; affects deployments where OVSDB is writable by untrusted parties.
Statement
Open vSwitch is vulnerable to denial of service via resource exhaustion in udpif_set_threads() due to a missing upper-bound check on thread counts. An attacker with high privileges (OVSDB write access) can configure excessive handler or revalidation threads to exhaust system resources. CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H (4.4). Affects FDP, OpenShift OVS RPMs, RHEL-7 ELS, and Fedora openvswitch packages.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 4.4 | N/A | 6.5 |
| Attack Vector | Local | N/A | Network |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | High | N/A | Low |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | None | N/A | None |
| Integrity Impact | None | N/A | None |
| Availability Impact | High | N/A | High |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
cve.org: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory); DoS: Resource Consumption (Other)
When allocating resources without limits, an attacker could prevent other systems, applications, or processes from accessing the same type of resource. It can be easy for an attacker to consume many resources by rapidly making many requests or causing larger resources to be used than is needed.
Frequently Asked Questions
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