CVE-2026-44687
3.7 · LOWOverview
CVE-2026-44687 is a low-severity vulnerability affecting nlnetlabs unbound. It was published on July 22, 2026 and has a CVSS 3.1 base score of 3.7 (LOW).
This vulnerability has a CVSS 3.1 base score of 3.7, rated LOW. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical Description
In NLnet Labs Unbound 1.13.2 up to and including 1.25.1, stub or forward zones where the name is below an intermediate labed below a DNSSEC signed zone could be shadowed by the intermediate label's secure NXDOMAIN answer from the parent. This is caused by an off-by-one error in 'harden-below-nxdomain' logic; enabled by default. It effectively bypasses the configuration and the configured stub/forward zone is never contacted. 'harden-below-nxdomain' does an upward DNS cache walk together with a delegation point guard that does not allow NXDOMAIN synthesis above stub/forward zones. The guard tests the domain name but before stripping a label. This results in an iteration where the domain name equals the configured stub/forward zone apex that passes the guard, strips one more label, and probes the cache at the apex's immediate public parent. If that parent has a cached DNSSEC-secure NXDOMAIN, which it will for any private namespace nested two or more labels under a signed public name, the
Remediation
Check the references section for vendor advisories and patches from nlnetlabs. Update unbound to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| nlnetlabs | unbound | >= 1.13.2, < 1.25.2 | Affected |
Frequently Asked Questions
What is CVE-2026-44687?
CVE-2026-44687 is a low-severity vulnerability affecting nlnetlabs unbound. It was published on July 22, 2026 and has a CVSS 3.1 base score of 3.7 (LOW).
How severe is CVE-2026-44687?
This vulnerability has a CVSS 3.1 base score of 3.7, rated LOW. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-44687?
Check the references section for vendor advisories and patches from nlnetlabs. Update unbound to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-44687?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-44687 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
Automated penetration testing that runs continuously, not just quarterly.
AI-driven PR review catches vulnerable dependencies before they ship.
Browser-based exploitation validates findings with real proof-of-concept.
Related LOW CVEs from 2026
View all →Improper handling of values in the microcode flow for some Intel(R) Processor Family may allow an es
A flaw was found in libsoup, a library used by applications to send network requests. This vulnerabi
A flaw was found in libsoup. A remote attacker, by controlling the method parameter of the `soup_mes
A flaw was found in libsoup. An attacker controlling the value used to set the Content-Type header c
OpenSC is an open source smart card tools and middleware. Prior to version 0.27.0, feeding a crafted
OpenSC is an open source smart card tools and middleware. Prior to version 0.27.0, sc_compacttlv_fin
Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and C
HCL BigFix Service Management (SM) is susceptible to a Root File System Not Mounted as Read-Only. An
FacturaScripts is an open source accounting and invoicing software. Versions 2025.7 and prior contai
An integer underflow in the volxlate function in Netatalk 3.0.0 through 4.4.2 allows a local privile
Capsule is a multi-tenancy and policy-based framework for Kubernetes. To defend against namespace hi
Improper input validation in Microsoft Azure Attestation service and Device Health Attestation Servi