CVE-2017-7543 — neutron
MEDIUMCVE-2017-7543 is a medium-severity (CVSS 5.9) CWE-362 vulnerability in neutron. A fix is available for neutron — see the affected versions and patch details below.
OpenStack Neutron Race Condition vulnerability
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2017-7543 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 378,567 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
neutron🐍neutron🐍neutron🐍neutronReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
A race-condition flaw was discovered in openstack-neutron before 7.2.0-12.1, 8.x before 8.3.0-11.1, 9.x before 9.3.1-2.1, and 10.x before 10.0.2-1.1, where, following a minor overcloud update, neutron security groups were disabled. Specifically, the following were reset to 0: net.bridge.bridge-nf-call-ip6tables and net.bridge.bridge-nf-call-iptables. The race was only triggered by an update, at which point an attacker could access exposed tenant VMs and network resources.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | neutron | all versions | 7.2.0-12.1pip install --upgrade 'neutron==7.2.0-12.1' |
| 🐍PyPI | neutron | ≥ 8.0.0&&< 8.3.0-11.1 | 8.3.0-11.1pip install --upgrade 'neutron==8.3.0-11.1' |
| 🐍PyPI | neutron | ≥ 9.0.0&&< 9.3.1-2.1 | 9.3.1-2.1pip install --upgrade 'neutron==9.3.1-2.1' |
| 🐍PyPI | neutron | ≥ 10.0.0&&< 10.0.2-1.1 | 10.0.2-1.1pip install --upgrade 'neutron==10.0.2-1.1' |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for neutron, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update neutron to 7.2.0-12.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2017-7543 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2017-7543 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2017-7543. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat Enterprise Linux OpenStack Platform 6.0 (Juno) for RHEL 7 | openstack-neutron-0:2014.2.3-42.el7ost | RHSA-2017:2452 |
| Red Hat Enterprise Linux OpenStack Platform 7.0 (Kilo) for RHEL 7 | openstack-neutron-0:2015.1.4-16.1.el7ost | RHSA-2017:2450 |
| Red Hat OpenStack Platform 10.0 (Newton) | openstack-neutron-1:9.3.1-2.1.el7ost | RHSA-2017:2448 |
| Red Hat OpenStack Platform 11.0 (Ocata) | openstack-neutron-1:10.0.2-1.1.el7ost | RHSA-2017:2449 |
| Red Hat OpenStack Platform 8.0 (Liberty) | openstack-neutron-1:7.2.0-12.1.el7ost | RHSA-2017:2451 |
| Red Hat OpenStack Platform 9.0 (Mitaka) | openstack-neutron-1:8.3.0-11.1.el7ost | RHSA-2017:2447 |
Frequently Asked Questions
Is CVE-2017-7543 in your dependencies?
O3 Security finds CVE-2017-7543 across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.