Skip to main content

Openstack CVE-2021-38598

CRITICAL
Authentication Bypass by Spoofing (CWE-290)
2021-08-23 cve@mitre.org
9.1
CVSS 3.1 · NVD
View

Vulnerability Assessment

Weakness
CWE
OWASP Top 10:2025
A07:2025 - Authentication Failures
ASVS 5.0
V6 - Authentication Anti-spoofing controls
MITRE ATT&CK

1 technique across 1 tactic: Defense Evasion

The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up.

Impact

CVSS score of 9.1 (CRITICAL). Attack characteristics: network attack vector, low complexity, no privileges required, no user interaction not required. Public proof-of-concept exploit code is available.

Exploit ScenarioDerived

This vulnerability can be exploited remotely over the network. Successful exploitation could compromise the critical-severity affected system.

Act Now Prioritize within 24-48h. Why: CRITICAL severity + public POC available.
Patch available 1.2% exploitation probability (EPSS)

Get an e-mail when this CVE is exploited, patched or re-scored. Free account.

Alert me

AnalysisAI

OpenStack Neutron before 16.4.1, 17.x before 17.1.3, and 18.0.0 allows hardware address impersonation when the linuxbridge driver with ebtables-nft is used on a Netfilter-based platform. Rated critical severity (CVSS 9.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.

RemediationAI

No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.

Affected Packages

pypi neutron fix: 16.4.1, 17.1.3, 18.1.0

Source: OSV (Open Source Vulnerabilities)

Affects your stack

Affects 1 package in pypi

Checking this CVE against your own stacks and servers is part of the Basic plan and up.

Technical ContextAI · show details

This vulnerability is classified under CWE-290. OpenStack Neutron before 16.4.1, 17.x before 17.1.3, and 18.0.0 allows hardware address impersonation when the linuxbridge driver with ebtables-nft is used on a Netfilter-based platform. By sending carefully crafted packets, anyone in control of a server instance connected to the virtual switch can impersonate the hardware addresses of other systems on the network, resulting in denial of service or in some cases possibly interception of traffic intended for other destinations. Affected products include: Openstack Neutron. Version information: before 16.4.1.

Know when Openstack gets its next vulnerability

  • Watch products and get an email when something new is published
  • Check this CVE against your own stack and servers
  • Exploit and PoC references, threat intelligence from 22 sources

No credit card · 7-day full trial

Severity by source

NVD PRIMARY 9.1 CRITICAL
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
High
Availability
High

DescriptionNVD

OpenStack Neutron before 16.4.1, 17.x before 17.1.3, and 18.0.0 allows hardware address impersonation when the linuxbridge driver with ebtables-nft is used on a Netfilter-based platform. By sending carefully crafted packets, anyone in control of a server instance connected to the virtual switch can impersonate the hardware addresses of other systems on the network, resulting in denial of service or in some cases possibly interception of traffic intended for other destinations.

Threat Intelligence Overview

EPSS Score
1.2%
Top 35% exploitable
Exploit
POC
Public exploit code exists
Data Quality
2 sources
Confidence: Low

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue
Severity CRITICAL
CISA KEV No
Public POC Yes
EPSS 1.2%
Patch available Yes
Active threat No
Deciding rule
CRITICAL severity + public POC available
What every action level means
Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.
Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.
This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.
This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.
Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

SSVC AssessmentENISA

SSVC Decision· derived
Scheduled
Exploitation· derived
Poc
System Exposure· derived
Open
Automatable· derived
Yes
Human Impact· derived
Medium

Priority Score

67
Low Medium High Critical
KEV: 0
EPSS: +1
CVSS: +46
PoC: +20
Weaponized: 0
Threat intel: 0
Gov advisory: 0

Attack Technique

Authentication bypass attacks exploit flaws in the verification mechanisms that control access to systems and applications.

Denial of Service attacks render applications or systems unavailable by overwhelming resources or triggering failure conditions.

Affected Products (CPE)NVD

cpe:2.3:a:openstack:neutron:*:*:*:*:*:*:*:*
cpe:2.3:a:openstack:neutron:*:*:*:*:*:*:*:*
cpe:2.3:a:openstack:neutron:18.0.0:*:*:*:*:*:*:*
CVE-2016-6662 CRITICAL POC
9.8 Sep 20

Oracle MySQL through 5.5.52, 5.6.x through 5.6.33, and 5.7.x through 5.7.15; MariaDB before 5.5.51, 10.0.x before 10.0.2

CVE-2013-2121 MEDIUM POC
6.0 Jul 31

Eval injection vulnerability in the create method in the Bookmarks controller in Foreman before 1.2.0-RC2 allows remote

CVE-2013-2113 MEDIUM POC
6.0 Jul 31

The create method in app/controllers/users_controller.rb in Foreman before 1.2.0-RC2 allows remote authenticated users w

CVE-2018-3639 MEDIUM POC
5.5 May 22

Systems with microprocessors utilizing speculative execution and speculative execution of memory reads before the addres

CVE-2015-3456 HIGH POC
7.7 May 13

The Floppy Disk Controller (FDC) in QEMU, as used in Xen 4.5.x and earlier and KVM, allows local guest users to cause a

CVE-2018-11218 CRITICAL POC
9.8 Jun 17

Memory Corruption was discovered in the cmsgpack library in the Lua subsystem in Redis before 3.2.12, 4.x before 4.0.10,

CVE-2015-8914 CRITICAL POC
9.1 Jun 17

The IPTables firewall in OpenStack Neutron before 7.0.4 and 8.0.0 through 8.1.0 allows remote attackers to bypass an int

CVE-2024-28718 CRITICAL POC
9.8 Apr 12

An issue in OpenStack magnum yoga-eom version allows a remote attacker to execute arbitrary code via the cert_manager.py

CVE-2018-11219 CRITICAL POC
9.8 Jun 17

An Integer Overflow issue was discovered in the struct library in the Lua subsystem in Redis before 3.2.12, 4.x before 4

CVE-2017-1000366 HIGH POC
7.8 Jun 19

glibc contains a vulnerability that allows specially crafted LD_LIBRARY_PATH values to manipulate the heap/stack, causin

CVE-2015-7512 CRITICAL
9.0 Jan 08

Buffer overflow in the pcnet_receive function in hw/net/pcnet.c in QEMU, when a guest NIC has a larger MTU, allows remot

CVE-2026-28370 CRITICAL POC
9.1 Feb 27

Code injection in OpenStack Vitrage query parser allows authenticated users to execute arbitrary Python code through cra

This site uses cookies essential for authentication and security. No tracking or analytics cookies are used. Privacy Policy