BlackTreeIndependent security intelligence

Full vulnerability report · 2026

CVE-2026-45673High confidence

Netty: DNS Cache Poisoning due to Predictable PRNG and Default Static Source Port

netty · netty

6.8MediumCVSS 3.1

Recommended action

Scheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Patch available

Distribution package intelligence

Ubuntu vendor package status

Canonical’s release and source-package findings are shown separately from local repository availability.

1 package state

Repository candidate not checked

A published vendor fix does not prove that a matching update is enabled and installable on a particular asset. Confirm the local package candidate before scheduling remediation.

Ubuntu release	Source package	Vendor state	Fixed version	Evidence
Ubuntu 24.04 LTSnoble · esm-apps	`netty`	Under evaluationCanonical reports that the package might be affected and still needs evaluation or fixing.	`Not published in this feed`	Canonical record ↗Source updated 8 Sept 2026

Direct vendor intelligence

Authoritative vendor CSAF and VEX advisories

Structured product status and remediation from the issuing vendor. Product-state explanations are always visible; large lists can be searched or downloaded.

1 current

CVE-2026-45673 · CSAF 2.0 · revision 3 · finalRed Hat Product Securitynetty-resolver-dns: Netty DNS resolver: DNS Cache Poisoning via predictable transaction IDs

43 known affected

The vendor explicitly identifies these products as affected by this CVE.

netty-resolver-dns as a component of Cryostat 4
openshift-serverless-1/kn-ekb-dispatcher-rhel9 as a component of OpenShift Serverless
openshift-serverless-1/kn-ekb-receiver-rhel9 as a component of OpenShift Serverless
openshift-serverless-1/kn-eventing-integrations-aws-ddb-streams-source-rhel9 as a component of OpenShift Serverless
openshift-serverless-1/kn-eventing-integrations-aws-s3-sink-rhel9 as a component of OpenShift Serverless
openshift-serverless-1/kn-eventing-integrations-aws-s3-source-rhel9 as a component of OpenShift Serverless
openshift-serverless-1/kn-eventing-integrations-aws-sns-sink-rhel9 as a component of OpenShift Serverless
openshift-serverless-1/kn-eventing-integrations-aws-sqs-sink-rhel9 as a component of OpenShift Serverless
openshift-serverless-1/kn-eventing-integrations-aws-sqs-source-rhel9 as a component of OpenShift Serverless
openshift-serverless-1/kn-eventing-integrations-log-sink-rhel9 as a component of OpenShift Serverless
openshift-serverless-1/kn-eventing-integrations-timer-source-rhel9 as a component of OpenShift Serverless
netty-resolver-dns as a component of Red Hat build of Apache Camel - HawtIO 4

Summary: A flaw was found in Netty's DNS resolver component. This vulnerability arises from the use of a predictable pseudo-random number generator (PRNG) for DNS transaction IDs and a static User Datagram Protocol (UDP) source port. This combination significantly reduces the randomness of DNS queries, making it easier for a remote attacker to perform DNS Cache Poisoning, also known as a Kaminsky attack. Successful exploitation could allow an attacker to redirect network traffic to malicious servers.
Remediation: Before applying the update, make sure all previously released errata relevant to your system have been applied. Also, back up your existing installation, including all applications, configuration files, databases and database settings. For details on how to apply this update, refer to: https://access.redhat.com/articles/11258

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current

ENISA EUVD identifier

EUVD-2026-36445

No EUVD known-exploited evidence

ENISA has published the identifier mapping but no EUVD description has been stored yet.

EUVD state: Present in the current official mapping
Known exploitation: Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score: Not supplied in the stored EUVD record
Advisory evidence: No linked advisory details stored yet

Recommended actionScheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Patch available

What, why and how

Netty is a network application framework for development of protocol servers and clients. Prior to versions 4.1.135.Final and 4.2.15.Final, Netty's DNS resolver uses a predictable PRNG for generating DNS transaction IDs and defaults to a static UDP source port. This combination reduces the entropy of DNS queries, enabling DNS Cache Poisoning (Kaminsky attack). Versions 4.1.135.Final and 4.2.15.Final patch the issue.

What

Why

The product uses insufficiently random numbers or values in a security context that depends on unpredictable numbers.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

Why

The product uses insufficiently random numbers or values in a security context that depends on unpredictable numbers.

How

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation

Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.

No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

Public PoC / exploit material

Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.

None recorded

No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.

Likely attack path: a network path → Use of Insufficiently Random Values → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface: Network
Privileges required: None: unauthenticated exploitation is possible
User interaction: None
Attack complexity: High: exploitation depends on specific conditions
Security boundary: Changed: exploitation can affect a different security authority
Weakness ? CWE means Common Weakness Enumeration: a standard category for the underlying weakness.: CWE-330 ↗
CWE-330: Use of Insufficiently Random Values. The product uses insufficiently random numbers or values in a security context that depends on unpredictable numbers.
CVSS vector ? CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:H/A:N
Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.
AVNetworkAttack vector: The vulnerable component can be reached over a network.ACHighAttack complexity: Successful exploitation depends on specific conditions outside the attacker's direct control.PRNonePrivileges required: The attacker does not need an account or existing privileges.UINoneUser interaction: No action by another user is required.SChangedScope: The attack can affect a component governed by a different security authority.CNoneConfidentiality impact: No direct loss is represented by this metric.IHighIntegrity impact: A successful attack can cause a major loss.ANoneAvailability impact: No direct loss is represented by this metric.
Post-exploitation / living off the land: No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.

NetworkUnauthenticatedCWE-330

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

ENISA EUVD · EUVD-2026-36445Official EUVD mapping

0 linked advisory records.

Official EUVD record

BSI · German · WID-SEC-W-2026-1814Netty: Mehrere Schwachstellen

Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Netty ausnutzen, um Sicherheitsvorkehrungen zu umgehen, Daten zu manipulieren, vertrauliche Informationen offenzulegen oder einen Denial-of-Service-Zustand herbeizuführen.

Official advisory

CERT-FR · French · CERTFR-2026-AVI-0933Multiples vulnérabilités dans les produits IBM

d?id=CVE-2026-42766 Référence CVE CVE-2026-42767 https://www.cve.org/CVERecord?id=CVE-2026-42767 Référence CVE CVE-2026-42770 https://www.cve.org/CVERecord?id=CVE-2026-42770 Référence CVE CVE-2026-44249 https://www.cve.org/CVERecord?id=CVE-2026-44249 Référence CVE CVE-2026-45409 https://www.cve.org/CVERecord?id=CVE-2026-45409 Référence CVE CVE-2026-45416 https://www.cve.org/CVERecord?id=CVE-2026-45416 Référence CVE CVE-2026-45445 https://www.cve.org/CVERecord?id=CVE-2026-45445 Référence CVE CVE-2026-45446 https://www.cve.org/CVERecord?id=CVE-2026-45446 Référence CVE CVE-2026-45447 https://www.cve.org/CVERecord?id=CVE-2026-45447 Référence CVE CVE-2026-45673 https://www.cve.org/CVERecord?id=CVE-2026-45673 Référence CVE CVE-2026-45674 https://www.cve.org/CVERecord?id=CVE-2026-45674 Référence CVE CVE-2026-47265 https://www.cve.org/CVERecord?id=CVE-2026-47265 Référence CVE CVE-2026-47691 https://www.cve.org/CVERecord?id=CVE-2026-47691 Référence CVE CVE-2026-48155 https://www.cve.org/CVERecord?id=CVE-2026-48155 Référence CVE CVE-2026-48156 https://www.cve.org/CVERecord?id=CVE-2026-48156 Référence CVE CVE-2026-48522 https://www.cve.org/CVERecord?id=CVE-2026-48522 Référence CVE CVE-2026-48523 https://www.cve.org/CVERecord?id=CVE-2026-48523 Référence CVE CVE-2026-48524 https://www.cve.org/CVERecord?id=

Official advisory

Patch and workaround

Operational remediation based on structured source evidence.

Status ? Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.: Patch available
Affected: netty-resolver-dns as a component of Cryostat 4; openshift-serverless-1/kn-ekb-dispatcher-rhel9 as a component of OpenShift Serverless; openshift-serverless-1/kn-ekb-receiver-rhel9 as a component of OpenShift Serverless; openshift-serverless-1/kn-eventing-integrations-aws-ddb-streams-source-rhel9 as a component of OpenShift Serverless; openshift-serverless-1/kn-eventing-integrations-aws-s3-sink-rhel9 as a component of OpenShift Serverless; openshift-serverless-1/kn-eventing-integrations-aws-s3-source-rhel9 as a component of OpenShift Serverless; openshift-serverless-1/kn-eventing-integrations-aws-sns-sink-rhel9 as a component of OpenShift Serverless; openshift-serverless-1/kn-eventing-integrations-aws-sqs-sink-rhel9 as a component of OpenShift Serverless; openshift-serverless-1/kn-eventing-integrations-aws-sqs-source-rhel9 as a component of OpenShift Serverless; openshift-serverless-1/kn-eventing-integrations-log-sink-rhel9 as a component of OpenShift Serverless; openshift-serverless-1/kn-eventing-integrations-timer-source-rhel9 as a component of OpenShift Serverless; netty-resolver-dns as a component of Red Hat build of Apache Camel - HawtIO 4; netty-resolver-dns as a component of Red Hat build of Apache Camel 4 for Quarkus 3; netty-resolver-dns as a component of Red Hat build of Apache Camel for Spring Boot 4; netty-resolver-dns as a component of Red Hat build of Apicurio Registry 3; netty-resolver-dns as a component of Red Hat build of Debezium 3; netty-resolver-dns as a component of Red Hat Build of Keycloak; rhbk-openshift-rhel9/rhbk-openshift-rhel9 as a component of Red Hat Build of Keycloak; rhbk-rhel9-operator/rhbk-rhel9-operator as a component of Red Hat Build of Keycloak; rhbk/keycloak-rhel9 as a component of Red Hat Build of Keycloak; rhbk/keycloak-rhel9-operator as a component of Red Hat Build of Keycloak; netty-resolver-dns as a component of Red Hat Data Grid 8; bazel6.src as a component of Red Hat Enterprise Linux AI (RHEL AI) 3; bazel7.src as a component of Red Hat Enterprise Linux AI (RHEL AI) 3; bazel8.src as a component of Red Hat Enterprise Linux AI (RHEL AI) 3; netty-resolver-dns as a component of Red Hat Fuse 7; netty-resolver-dns as a component of Red Hat JBoss Enterprise Application Platform 7; netty-resolver-dns as a component of Red Hat JBoss Enterprise Application Platform 8; netty-resolver-dns as a component of Red Hat JBoss Enterprise Application Platform Expansion Pack; rhoai/odh-spark-operator-rhel9 as a component of Red Hat OpenShift AI (RHOAI); and 13 more
Fixed: Red Hat JBoss Enterprise Application Platform 8.1; Red Hat build of Quarkus 3.27.4.SP1; Red Hat build of Quarkus 3.33.2.SP1
Action: Before applying the update, make sure all previously released errata relevant to your system have been applied. Also, back up your existing installation, including all applications, configuration files, databases and database settings. For details on how to apply this update, refer to: https://access.redhat.com/articles/11258
Workaround: No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.

Evidence and provenance

Published 12 Jun 2026 · Last source change 12 Jun 2026, 16:05 UTC · CWE-330 · Use of Insufficiently Random Values

CVE recordCVE.org · 5.2

CVSS sourceCNA

EPSS source

The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.

FIRST · tracked since 2026-08-14

European sourceENISA EUVD · EUVD-2026-36445

Product sourceVendor CSAF · Red Hat Product Security

Remediation sourceVendor CSAF · Red Hat Product Security

CWE sourceCNA

NVD statusNVD enriched

Core structured fields are present and their contributing authorities are shown above.

Material change intelligence

What changed after publication

View recent updates →

No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.

2026-06-12CVE published

ENISA EUVD · EUVD-2026-36445↗Vendor CSAF · Red Hat Product Security↗CVE authority or vendor reference↗Official CVE record (CNA and ADP data)↗NVD record↗

Technical terms and abbreviations used in this report

CVE: Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS: Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS: Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE: Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA: CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP: Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD: National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT: A computer security incident response team that publishes warnings or coordinates incident response.
PoC: Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF: Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL: Living off the land: abuse of legitimate tools or system functions during an attack.