CVE-2026-71194
OpenStack Designate mDNS Handler Denial of Service Vulnerability
Description
In OpenStack Designate before 22.0.2, the mDNS handler performs pool-blind lookups when resolving record queries and NOTIFY requests. When two zones with the same name exist across different pools, the lookup fails with a deterministic error, causing the handler to return REFUSED for all DNS queries through that path. The _handle_notify path is exploitable via a single unauthenticated UDP packet. This is independently reachable through the cross-tenant zone overlap described in a different recent CVE, and also affects legitimate same-tenant cross-pool configurations. BIND9 views do not mitigate this issue as mDNS is a shared service upstream of any view configuration.
INFO
Published Date :
Aug. 12, 2026, 11:17 p.m.
Last Modified :
Aug. 12, 2026, 11:17 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | 8254265b-2729-46b6-b9e3-3dfca2d5bfca | ||||
| CVSS 3.1 | MEDIUM | [email protected] |
Solution
- Update OpenStack Designate to version 22.0.2 or later.
- Apply relevant security patches for affected versions.
- Review DNS zone configurations for cross-pool overlaps.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-71194.
| URL | Resource |
|---|---|
| https://launchpad.net/bugs/2160533 | |
| https://security.openstack.org/ossa/OSSA-2026-034.html | |
| https://www.openwall.com/lists/oss-security/2026/08/11/6 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-71194 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-71194
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-71194 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-71194 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Aug. 12, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://opendev.org/openstack/designate', 'vendor': 'OpenStack', 'product': 'Designate', 'versions': [{'status': 'affected', 'version': '1.0.0', 'lessThan': '20.0.2', 'versionType': 'semver'}, {'status': 'affected', 'version': '21.0.0', 'lessThan': '21.0.1', 'versionType': 'semver'}, {'status': 'affected', 'version': '22.0.0', 'lessThan': '22.0.2', 'versionType': 'semver'}], 'defaultStatus': 'unaffected'}] Added Description In OpenStack Designate before 22.0.2, the mDNS handler performs pool-blind lookups when resolving record queries and NOTIFY requests. When two zones with the same name exist across different pools, the lookup fails with a deterministic error, causing the handler to return REFUSED for all DNS queries through that path. The _handle_notify path is exploitable via a single unauthenticated UDP packet. This is independently reachable through the cross-tenant zone overlap described in a different recent CVE, and also affects legitimate same-tenant cross-pool configurations. BIND9 views do not mitigate this issue as mDNS is a shared service upstream of any view configuration. Added CVSS V3.1 AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:H Added CWE CWE-669 Added Reference https://launchpad.net/bugs/2160533 Added Reference https://security.openstack.org/ossa/OSSA-2026-034.html Added Reference https://www.openwall.com/lists/oss-security/2026/08/11/6