CVE-2017-7543

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.

Published: 2018-07-26 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2017-7543 is rated Moderate Risk (49.2/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 1.85%). EPSS rose +1.37% over the last day, indicating growing attacker interest. Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2017-7543

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.48% 1.85% +1.37%
2 2025-12-14 0.21% 0.48% +0.27%
3 2025-11-21 — 0.21% —

Full EPSS history (21 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2017-7543

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.3 3.0 MEDIUM
CVSS:3.0/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 1.6 3.6 [email protected]
5.9 3.0 MEDIUM
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 2.2 3.6 [email protected]
4.3 2.0 MEDIUM
AV:N/AC:M/Au:N/C:P/I:N/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:N)
No availability impact.
 8.6 2.9 [email protected]

Weakness enumeration for CVE-2017-7543

GitHub Security Advisory for CVE-2017-7543

GHSA-hvxr-2fvv-c3wq · Severity: medium · Ecosystem: pip — OpenStack Neutron Race Condition vulnerability

OS Trackers for CVE-2017-7543

vendor priority summary link
debian unimportant CVE-2017-7543 unimportant priority: Debian including 1 source packages (neutron), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2017-7543
redhat high — https://access.redhat.com/security/cve/CVE-2017-7543
suse medium CVE-2017-7543 severity moderate: SUSE including 14 source package names (openstack-neutron, openstack-neutron-dhcp-agent, …), 24 product×package rows across 2 product lines (SUSE OpenStack Cloud 6, SUSE OpenStack Cloud 7): Known Not Affected 24. https://www.suse.com/security/cve/CVE-2017-7543/
ubuntu medium CVE-2017-7543 medium priority: Ubuntu including 1 source packages (neutron), 4 status rows across 4 suites (trusty, upstream, xenial, zesty): not-affected 2, DNE 1, needs-triage 1. https://ubuntu.com/security/CVE-2017-7543

Affected software / configurations for CVE-2017-7543

Vendor Product Version Raw CPE
openstack neutron >= 7.0.0, < 7.2.0-12.1 cpe:2.3:a:openstack:neutron:*:*:*:*:*:*:*:*
openstack neutron >= 8.0.0, < 8.3.0-11.1 cpe:2.3:a:openstack:neutron:*:*:*:*:*:*:*:*
openstack neutron >= 9.0.0, < 9.3.1-2.1 cpe:2.3:a:openstack:neutron:*:*:*:*:*:*:*:*
openstack neutron >= 10.0.0, < 10.0.2-1.1 cpe:2.3:a:openstack:neutron:*:*:*:*:*:*:*:*
redhat openstack 6.0 cpe:2.3:a:redhat:openstack:6.0:*:*:*:*:*:*:*
redhat openstack 7.0 cpe:2.3:a:redhat:openstack:7.0:*:*:*:*:*:*:*
redhat openstack 8 cpe:2.3:a:redhat:openstack:8:*:*:*:*:*:*:*
redhat openstack 9 cpe:2.3:a:redhat:openstack:9:*:*:*:*:*:*:*
redhat openstack 10 cpe:2.3:a:redhat:openstack:10:*:*:*:*:*:*:*
redhat openstack 11 cpe:2.3:a:redhat:openstack:11:*:*:*:*:*:*:*

References for CVE-2017-7543

cvelogic Threat Intelligence