CVE-2026-40209
Last modified
CVE-2026-40209 is a medium-severity vulnerability rated 5.3/10 on the CVSS scale. An attacker might be able to cause outgoing TCP connections to backend to be stuck until a timeout occurs instead of being released immediately, by sending IXFR queries. This could be used to cause a denial of service if there is a limit to the number of concurrent connections to this backend, or if the process runs out of file descriptors.. EPSS estimates a 0.40% chance of exploitation in the next 30 days.
Description
An attacker might be able to cause outgoing TCP connections to backend to be stuck until a timeout occurs instead of being released immediately, by sending IXFR queries. This could be used to cause a denial of service if there is a limit to the number of concurrent connections to this backend, or if the process runs out of file descriptors.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Weakness Enumeration
References
Timeline
- Published
- Last Modified
- Status
- Deferred
Frequently Asked Questions
What is CVE-2026-40209?
How severe is CVE-2026-40209?
How do I fix CVE-2026-40209?
How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
- Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
- AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.
Related CVEs from 2026
- CVE-2026-40198Net::CIDR::Lite versions before 0.23 for Perl does not valid…7.5
- CVE-2026-40199Net::CIDR::Lite versions before 0.23 for Perl mishandles IPv…6.5
- CVE-2026-4020The Gravity SMTP plugin for WordPress is vulnerable to Sensi…7.5
- CVE-2026-40200An issue was discovered in musl libc 0.7.10 through 1.2.6. S…8.1
- CVE-2026-40201@diplodoc/search-extension 1.0.0 through 3.x before 3.0.3 al…5.4
- CVE-2026-40208An attacker might be able to delay the processing of DoH3 qu…3.7
- CVE-2026-4021The Contest Gallery plugin for WordPress is vulnerable to an…8.1
- CVE-2026-40210An out-of-bounds read might happen when SetMacAddrAction is …4.8
- CVE-2026-40211An attacker can send crafted DNS over HTTP/3 queries, trigge…5.3
- CVE-2026-40212OpenStack Skyline before 5.0.1, 6.0.0, and 7.0.0 has a DOM-b…5.4
- CVE-2026-40213OpenStack Cyborg before 16.0.1 uses rule:allow (check_str='@…7.4
- CVE-2026-40214In OpenStack Cyborg before 16.0.1, the Accelerator Request (…6.3
Are you affected by CVE-2026-40209?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST