Improper Input Validation

published 2021-06-02 5 y ago modified 2026-06-17 4 mo ago also GHSA-57v4-m9jx-mh8r , EUVD-2021-1266

cvss: 5.6; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 0.8%; EPSS 0.8% chance of exploitation in 30 days, percentile 56%
public exploits: 0; none known

A vulnerability was found in OVN Kubernetes in versions up to and including 0.3.0 where the Egress Firewall does not reliably apply firewall rules when there is multiple DNS rules. It could lead to potentially lose of confidentiality, integrity or availability of a service.

Patch / fix

links 1

github.com/ovn-org/ovn-kubernetes#2169 pull request

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2021-3499 updated 2026-06-26 cvss 5.6

openshift/ovn-kubernetes: Egress Firewall does not reliably apply firewall rules

Red Hat OpenShift Container Platform 4.7 openshift4/ose-tests v4.7.0-202105110735.p0, openshift4/ose-console v4.7.0-202105070703.p0, openshift4/ose-jenkins v4.7.0-202105071334.p0, openshift4/ose-hyperkube v4.7.0-202105091821.p0, openshift4/ose-installer v4.7.0-202105101449.p0, openshift4/ose-sdn-rhel8 v4.7.0-202104280847.p0, +30 more
fixed: vendor fix RHBA-2021:1550

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

0.80% chance of exploitation in the next 30 days, higher than 56% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
NVD	3.1	5.6	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L
NVD	2.0	6.8	AV:N/AC:M/Au:N/C:P/I:P/A:P
GitHub	3.1	5.6	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L

Affected packages

ecosystem	package	affected	fixed in
go	github.com/ovn-org/ovn-kubernetes	<=0.3.0	no fix listed

Affected products

n/a openshift/ovn-kubernetes

Classification

Weakness

CWE-863 Incorrect Authorization

References

github.com /ovn-org/ovn-kubernetes/pull/2169
web
bugzilla.redhat.com /show_bug.cgi?id=1949188
web, issue-tracking, third-party-advisory
nvd.nist.gov /vuln/detail/CVE-2021-3499
advisory
access.redhat.com /errata/RHBA-2021:1550
web
access.redhat.com /security/cve/CVE-2021-3499
web

Sources

CVE List CVE-2021-3499
GitHub Advisory GHSA-57v4-m9jx-mh8r
NVD CVE-2021-3499

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary