Important: Red Hat Security Advisory: Red Hat Hardened Images RPMs bug fix and enhancement update

An update for Red Hat Hardened Images RPMs is now available. This update includes the following RPMs: unbound: python3-unbound-1.25.1-0.1.hum1 aarch64, x8664 unbound-1.25.1-0.1.hum1 aarch64, x8664 unbound-anchor-1.25.1-0.1.hum1 aarch64, x8664 unbound-devel-1.25.1-0.1.hum1 aarch64, x8664...

unbound: Unbound DNSSEC Validator Use-After-Free via Deep Copy Pointer Overwrite Leading to DoS and Possible Remote Code Execution

A flaw was discovered in Unbound’s DNSSEC validator can leave it using an invalid memory pointer after certain DS sub-query validations fail due to NSEC3 budget exhaustion. This may cause crashes and could potentially allow arbitrary code execution...

unbound: Unbound: Denial of Service due to locking inconsistency during RPZ XFR reload

A flaw was found in Unbound. When operating in a multi-threaded configuration with specific Response Policy Zones RPZ using 'rpz-nsip' or 'rpz-nsdname' triggers, a locking inconsistency during an RPZ zone transfer XFR reload can occur. This timing issue may allow an adversary to trigger a heap...

USN-8282-1 unbound vulnerabilities

Andrew Griffiths discovered that Unbound did not properly handle certain DNSCrypt packets. A remote attacker could possibly use this issue to cause Unbound to crash, resulting in a denial of service. CVE-2026-32792 Qifan Zhang discovered that Unbound incorrectly handled DNSSEC validation in certa...

CVE-2026-42959

A flaw was found in Unbound's DNSSEC validator when constructing chase-reply messages for validation. The code uses the wrong counter to calculate write offsets for ADDITIONAL section resource record sets. When a DNAME chain is combined with authority filtering, an uninitialized array slot is...

CVE-2026-42944

A flaw was found in Unbound, a Domain Name System DNS resolver. A remote attacker could trigger a heap overflow by sending specially crafted DNS reply packets. This occurs when Unbound attempts to encode multiple Name Server Identifier NSID or Extension Mechanisms for DNS EDNS Cookie options, or...

CVE-2026-33278

A flaw was discovered in Unbound’s DNSSEC validator can leave it using an invalid memory pointer after certain DS sub-query validations fail due to NSEC3 budget exhaustion. This may cause crashes and could potentially allow arbitrary code execution...

CVE-2026-42960

NLnet Labs Unbound up to and including version 1.25.0 is vulnerable to poisoning via promiscuous records for the authority section. Promiscuous RRSets that complement DNS replies in the authority section can be used to trick Unbound to cache such records. If an adversary is able to attach such...

ALPINE-CVE-2026-44608

NLnet Labs Unbound 1.14.0 up to and including version 1.25.0 has a locking inconsistency vulnerability that when certain conditions are met multi-threaded, RPZ XFR reload, RPZ zone with 'rpz-nsip'/'rpz-nsdname' triggers it could result in heap use-after-free and eventual crash. An adversary can...

CVE-2026-42960

NLnet Labs Unbound up to and including version 1.25.0 is vulnerable to poisoning via promiscuous records for the authority section. Promiscuous RRSets that complement DNS replies in the authority section can be used to trick Unbound to cache such records. If an adversary is able to attach such...

CVE-2026-44390

NLnet Labs Unbound up to and including version 1.25.0 has a vulnerability when handling replies with very large RRsets that Unbound needs to perform name compression for. Malicious upstream responses with very large RRsets with records that don't share a suffix above the root can cause Unbound to...

CVE-2026-44608

NLnet Labs Unbound 1.14.0 up to and including version 1.25.0 has a locking inconsistency vulnerability that when certain conditions are met multi-threaded, RPZ XFR reload, RPZ zone with 'rpz-nsip'/'rpz-nsdname' triggers it could result in heap use-after-free and eventual crash. An adversary can...

CVE-2026-44390

NLnet Labs Unbound up to and including version 1.25.0 has a vulnerability when handling replies with very large RRsets that Unbound needs to perform name compression for. Malicious upstream responses with very large RRsets with records that don't share a suffix above the root can cause Unbound to...

CVE-2026-44608

NLnet Labs Unbound 1.14.0 up to and including version 1.25.0 has a locking inconsistency vulnerability that when certain conditions are met multi-threaded, RPZ XFR reload, RPZ zone with 'rpz-nsip'/'rpz-nsdname' triggers it could result in heap use-after-free and eventual crash. An adversary can...

ALPINE-CVE-2026-42960

NLnet Labs Unbound up to and including version 1.25.0 is vulnerable to poisoning via promiscuous records for the authority section. Promiscuous RRSets that complement DNS replies in the authority section can be used to trick Unbound to cache such records. If an adversary is able to attach such...

ALPINE-CVE-2026-44390

NLnet Labs Unbound up to and including version 1.25.0 has a vulnerability when handling replies with very large RRsets that Unbound needs to perform name compression for. Malicious upstream responses with very large RRsets with records that don't share a suffix above the root can cause Unbound to...

CVE-2026-42534

NLnet Labs Unbound up to and including version 1.25.0 has a vulnerability in the jostle logic that could defeat its purpose and degrade resolution performance. Retransmits of the same query could renew the age of slow running queries and not allow the jostle logic to see them as aged and potentia...

CVE-2026-42923

NLnet Labs Unbound up to and including version 1.25.0 has a vulnerability in the DNSSEC validator where the code path to consult the negative cache for DS records does not take into account the limit on NSEC3 hash calculations introduced in 1.19.1. This leads to degradation of service during the...

CVE-2026-42944

NLnet Labs Unbound 1.14.0 up to and including version 1.25.0 has a vulnerability that results in heap overflow when encoding multiple NSID and/or DNS Cookie EDNS and/or EDNS Padding options in the reply packet. The relevant options 'nsid', 'answer-cookie', 'pad-responses' default need to be enabl...

CVE-2026-42923

NLnet Labs Unbound up to and including version 1.25.0 has a vulnerability in the DNSSEC validator where the code path to consult the negative cache for DS records does not take into account the limit on NSEC3 hash calculations introduced in 1.19.1. This leads to degradation of service during the...