Summary
OpenStack Neutron's unsupported dport option prevents applying security groups
An issue was discovered in the iptables firewall module in OpenStack Neutron before 10.0.8, 11.x before 11.0.7, 12.x before 12.0.6, and 13.x before 13.0.3. By setting a destination port in a security group rule along with a protocol that doesn't support that option (for example, VRRP), an authenticated user may block further application of security group rules for instances from any project/tenant on the compute hosts to which it's applied. (Only deployments using the iptables security group driver are affected.)
Impact
CVE-2019-9735 has a CVSS score of 6.5 (High). The vector is network-reachable, low privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (10.0.8, 11.0.7, 12.0.6, 13.0.3); upgrading removes the vulnerable code path.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
Already deployed Kodem?
See it in your environmentNew to Kodem? Get a demo →Remediation advice
neutron to 10.0.8 or later; neutron to 11.0.7 or later; neutron to 12.0.6 or later; neutron to 13.0.3 or later
Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.
Frequently Asked Questions
- What is CVE-2019-9735? CVE-2019-9735 is a high-severity security vulnerability in neutron (pip), affecting versions < 10.0.8. It is fixed in 10.0.8, 11.0.7, 12.0.6, 13.0.3.
- How severe is CVE-2019-9735? CVE-2019-9735 has a CVSS score of 6.5 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which versions of neutron are affected by CVE-2019-9735? neutron (pip) versions < 10.0.8 is affected.
- Is there a fix for CVE-2019-9735? Yes. CVE-2019-9735 is fixed in 10.0.8, 11.0.7, 12.0.6, 13.0.3. Upgrade to this version or later.
- Is CVE-2019-9735 exploitable, and should I be worried? Whether CVE-2019-9735 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2019-9735 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2019-9735?
- Upgrade
neutronto 10.0.8 or later - Upgrade
neutronto 11.0.7 or later - Upgrade
neutronto 12.0.6 or later - Upgrade
neutronto 13.0.3 or later
- Upgrade