CVE-2026-55973

A flaw was found in Unbound. When the 'dns-error-reporting: yes' option is enabled, a remote attacker can send a specially crafted DNS response containing a malformed EDNS Report-Channel option from a delegated zone they control. This can lead to a stack variable overwrite, causing the Unbound...

Linux Distros Unpatched Vulnerability : CVE-2026-55973

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available. - In NLnet Labs Unbound 1.23.0 up to and including 1.25.1, when 'dns-error-reporting: yes' is set, the EDNS Report-Channel option code 18 from the last upstream...

CVE-2026-55973

In NLnet Labs Unbound 1.23.0 up to and including 1.25.1, when 'dns-error-reporting: yes' is set, the EDNS Report-Channel option code 18 from the last upstream response is read and uses the option's length as the length of the agent domain. When a domain name check is performed on the agent domain...

CVE-2026-55973

In NLnet Labs Unbound 1.23.0 up to and including 1.25.1, when 'dns-error-reporting: yes' is set, the EDNS Report-Channel option code 18 from the last upstream response is read and uses the option's length as the length of the agent domain. When a domain name check is performed on the agent domain...

CVE-2026-55973 'dns-error-reporting: yes' leads to stack buffer overflow

In NLnet Labs Unbound 1.23.0 up to and including 1.25.1, when 'dns-error-reporting: yes' is set, the EDNS Report-Channel option code 18 from the last upstream response is read and uses the option's length as the length of the agent domain. When a domain name check is performed on the agent domain...

CVE-2026-55973

CVE-2026-55973 affects NLnet Labs Unbound 1.23.0 through 1.25.1. When dns-error-reporting: yes is enabled, the EDNS Report-Channel option (code 18) length from the last upstream response is treated as the length of the agent domain. If the agent domain contains garbage after the domain, those byt...

CVE-2026-55973 'dns-error-reporting: yes' leads to stack buffer overflow

In NLnet Labs Unbound 1.23.0 up to and including 1.25.1, when 'dns-error-reporting: yes' is set, the EDNS Report-Channel option code 18 from the last upstream response is read and uses the option's length as the length of the agent domain. When a domain name check is performed on the agent domain...

PT-2026-63389

Name of the Vulnerable Software and Affected Versions NLnet Labs Unbound versions 1.23.0 through 1.25.1 Description When the dns-error-reporting: yes setting is enabled, the software incorrectly processes the EDNS Report-Channel option code 18 from upstream responses. Specifically, it uses the...