Netty's HttpObjectDecoder skips arbitrary initial control characters when only initial CRLF characters are permitted
netty · netty
Official source article: GitHub GHSA-HVCG-QMG6-JM4C ↗. Check the applicable product and release in the original source.
5.3MediumCVSS 3.1
Recommended action
Patch only the product branches with a verified fix
Medium technical severity with public exploit material referenced by a structured source; prioritise exposed affected systems while verifying vendor guidance. Verified remediation exists for at least one product or source, but 4 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.
Published severityMedium→Operational priority:High, raised one band.upgradedsince 12 Jun 2026
Evidence used
No CISA KEV confirmation is currently recorded.
A structured source references public exploit or proof-of-concept material.
The selected CVSS metric records a network-reachable, unauthenticated path with no user interaction.
EPSS is 0.40% for the current model date.
Compensating controls
Validate the affected product branch and deploy the verified fixed release.
Restrict the affected network interface to trusted sources where business-safe.
Increase monitoring for the attack path and post-exploitation behaviour described in the report.
Verification
Confirm that the asset runs netty netty and falls inside the recorded affected range.
Verify the installed build against the product-specific fixed version after deployment.
Validate exposure, authentication requirements and compensating controls in the actual environment.
Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Cross-source reconciliation
Remediation availability differs by product scope
Verified remediation exists for at least one product or source, but 4 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.
Debian Security Tracker: 4 affected package states with no published fix
Distribution package intelligence
Release-specific package status
Debian, ubuntu findings are scoped to the named distribution, release and source package. An absent finding does not mean a package is unaffected.
5 package states
Package result overrides the generic status
BlackTree has verified remediation for at least one product or source, but the relevant distribution still reports no fixed package for 4 affected package states shown here. Treat those rows as affected with no fix until that distribution publishes a fixed version.
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.
Distribution release
Source package
Vendor state
Fixed version
Evidence
Debian trixietrixie · source
netty
Affected, no fix publishedDebian currently tracks this release as open.
These OSV and GitHub advisory ranges apply only to the named package and ecosystem. A listed fixed version is not a universal product patch or proof that an update is installed.
Structured product status and remediation from the issuing vendor. Product-state explanations are always visible; large lists can be searched or downloaded.
The vendor explicitly states that these products are not affected by this CVE.
netty-tcnative as component of SUSE Linux Enterprise Desktop 15 SP7
netty3 as component of SUSE Linux Enterprise Desktop 15 SP7
netty-tcnative as component of SUSE Linux Enterprise High Performance Computing 15 SP2
netty3 as component of SUSE Linux Enterprise High Performance Computing 15 SP2
netty-tcnative as component of SUSE Linux Enterprise High Performance Computing 15 SP3
netty3 as component of SUSE Linux Enterprise High Performance Computing 15 SP3
netty-tcnative as component of SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS
netty3 as component of SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS
netty-tcnative as component of SUSE Linux Enterprise High Performance Computing 15 SP4
netty3 as component of SUSE Linux Enterprise High Performance Computing 15 SP4
netty-tcnative as component of SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS
netty3 as component of SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS
Summary
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, before reading the first request-line, `HttpObjectDecoder` skips every byte for which `Character.isISOControl(b)` is `true` (0x00-0x1F and 0x7F) as well as all whitespace. RFC 9112 2.2 only asks servers to ignore empty CRLF lines preceding the request-line - a carefully scoped robustness allowance intended to handle HTTP/1.0 POST workarounds. Silently absorbing NUL bytes, SOH, STX, and other non-CRLF control characters goes significantly beyond this, and can be exploited for request-boundary confusion in pipelined or multiplexed transports where a front-end component treats those bytes differently. Versions 4.1.135.Final and 4.2.15.Final patch the issue.
Remediation
To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".
CVE-2026-50020 · CSAF 2.0 · revision 3 · finalRed Hat Product Securitynetty-codec-http: Netty: Data manipulation via request-boundary confusion in HttpObjectDecoder
45 known affected
The vendor explicitly identifies these products as affected by this CVE.
netty-codec-http 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-codec-http as a component of Red Hat AMQ Broker 7
Summary
A flaw was found in Netty. The HttpObjectDecoder component, which processes incoming HTTP requests, incorrectly skips certain control characters and whitespace before reading the first request line. This behavior, which goes beyond standard HTTP protocol requirements, can lead to request-boundary confusion in systems that use pipelined or multiplexed transports. An attacker could exploit this to cause a front-end component to misinterpret HTTP request boundaries, potentially resulting in low integrity impact, such as unintended data manipulation.
Remediation
Before applying this update, make sure all previously released errata relevant to your system have been applied. For details on how to apply this update, refer to: https://access.redhat.com/articles/11258
Optional official sources
National CERT insights ?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.
Choose official national sources for this report. Each advisory shows its original language. Your selection is remembered on this device and included in shared links.
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-2026-36468
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 actionPatch only the product branches with a verified fix
Medium technical severity with public exploit material referenced by a structured source; prioritise exposed affected systems while verifying vendor guidance. Verified remediation exists for at least one product or source, but 4 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.
Fix availability varies by product
01
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, before reading the first request-line, `HttpObjectDecoder` skips every byte for which `Character.isISOControl(b)` is `true` (0x00–0x1F and 0x7F) as well as all whitespace. RFC 9112 §2.2 only asks servers to ignore empty CRLF lines preceding the request-line — a carefully scoped robustness allowance intended to handle HTTP/1.0 POST workarounds. Silently absorbing NUL bytes, SOH, STX, and other non-CRLF control characters goes significantly beyond this, and can be exploited for request-boundary confusion in pipelined or multiplexed transports where a front-end component treats those bytes differently. Versions 4.1.135.Final and 4.2.15.Final patch the issue.
What
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, before reading the first request-line, `HttpObjectDecoder` skips every byte for which `Character.isISOControl(b)` is `true` (0x00–0x1F and 0x7F) as well as all whitespace. RFC 9112 §2.2 only asks servers to ignore empty CRLF lines preceding the request-line — a carefully scoped robustness allowance intended to handle HTTP/1.0 POST workarounds. Silently absorbing NUL bytes, SOH, STX, and other non-CRLF control characters goes significantly beyond this, and can be exploited for request-boundary confusion in pipelined or multiplexed transports where a front-end component treats those bytes differently. Versions 4.1.135.Final and 4.2.15.Final patch the issue.
Why
The product acts as an intermediary HTTP agent (such as a proxy or firewall) in the data flow between two entities such as a client and server, but it does not interpret malformed HTTP requests or responses in ways that are consistent with how the messages will be processed by those entities that are at the ultimate destination.
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
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, before reading the first request-line, `HttpObjectDecoder` skips every byte for which `Character.isISOControl(b)` is `true` (0x00–0x1F and 0x7F) as well as all whitespace. RFC 9112 §2.2 only asks servers to ignore empty CRLF lines preceding the request-line — a carefully scoped robustness allowance intended to handle HTTP/1.0 POST workarounds. Silently absorbing NUL bytes, SOH, STX, and other non-CRLF control characters goes significantly beyond this, and can be exploited for request-boundary confusion in pipelined or multiplexed transports where a front-end component treats those bytes differently. Versions 4.1.135.Final and 4.2.15.Final patch the issue.
Why
The product acts as an intermediary HTTP agent (such as a proxy or firewall) in the data flow between two entities such as a client and server, but it does not interpret malformed HTTP requests or responses in ways that are consistent with how the messages will be processed by those entities that are at the ultimate destination.
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.
02
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.Reference recorded
CISA Vulnrichment records proof-of-concept exploitation in its SSVC data. BlackTree has not independently executed or validated exploit material.
Likely attack path
a network path → Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') → 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
Low: no specialised conditions are recorded
Security boundary
Unchanged: impact remains within the vulnerable component's security authority
Weakness ?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-444: Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling'). The product acts as an intermediary HTTP agent (such as a proxy or firewall) in the data flow between two entities such as a client and server, but it does not interpret malformed HTTP requests or responses in ways that are consistent with how the messages will be processed by those entities that are at the ultimate destination.
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:L/PR:N/UI:N/S:U/C:N/I:L/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.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRNonePrivileges required: The attacker does not need an account or existing privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CNoneConfidentiality impact: No direct loss is represented by this metric.ILowIntegrity impact: A successful attack can cause a limited 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.
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 ↗BSI · German · WID-SEC-2026-3047IBM Planning Analytics: Mehrere Schwachstellen
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in IBM Planning Analytics ausnutzen, um einen Denial of Service Angriff durchzuführen oder Daten zu manipulieren.
Official advisory ↗CERT-FR · French · CERTFR-2026-AVI-1206Multiples vulnérabilités dans les produits IBM
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.
Use the product-specific evidence above. Patch only products with a verified fixed release, and keep every affected or under-investigation state without a matching fix in the remediation queue.
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.
04
Evidence and provenance
Published 12 Jun 2026 · Last source change 12 Jun 2026, 15:56 UTC · CWE-444 · Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
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-2026-36468
Product sourceCNA
Remediation sourceVendor CSAF · SUSE Product Security Team
CWE sourceCNA
NVD statusNVD enriched
Core structured fields are present and their contributing authorities are shown above.
Affected versionsThe structured affected or fixed version information changed.
Before
>= 4.2.0.Final, < 4.2.15.Final; < 4.1.135.Final · Fixed: 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
After
>= 4.2.0.Final, < 4.2.15.Final; < 4.1.135.Final · Fixed: Before applying this update, make sure all previously released errata relevant to your system have been applied. For details on how to apply this update, refer to: https://access.redhat.com/articles/11258
Affected versionsThe structured affected or fixed version information changed.
Before
netty-codec-http 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-codec-http as a component of Red Hat AMQ Broker 7; netty-codec-http as a component of Red Hat AMQ Clients; netty-codec-http as a component of Red Hat build of Apache Camel - HawtIO 4; netty-codec-http as a component of Red Hat build of Apache Camel 4 for Quarkus 3; netty-codec-http as a component of Red Hat build of Apache Camel for Spring Boot 4; netty-codec-http as a component of Red Hat build of Apicurio Registry 3; netty-codec-http as a component of Red Hat build of Debezium 3; netty-codec-http 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-codec-http as a component of Red Hat Data Grid 8; netty-codec-http as a component of Red Hat Fuse 7; netty-codec-http as a component of Red Hat JBoss Enterprise Application Platform 7; netty-codec-http as a component of Red Hat JBoss Enterprise Application Platform 8; netty-codec-http as a component of Red Hat JBoss Enterprise Application Platform Expansion Pack; rhoai/odh-modelmesh-rhel9 as a component of Red Hat OpenShift AI (RHOAI); rhoai/odh-openvino-model-server-rhel9 as a component of Red Hat OpenShift AI (RHOAI); and 15 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
After
netty-codec-http 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-codec-http as a component of Red Hat AMQ Broker 7; netty-codec-http as a component of Red Hat AMQ Clients; netty-codec-http as a component of Red Hat build of Apache Camel - HawtIO 4; netty-codec-http as a component of Red Hat build of Apache Camel 4 for Quarkus 3; netty-codec-http as a component of Red Hat build of Apache Camel for Spring Boot 4; netty-codec-http as a component of Red Hat build of Apicurio Registry 3; netty-codec-http as a component of Red Hat build of Debezium 3; netty-codec-http 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-codec-http as a component of Red Hat Data Grid 8; netty-codec-http as a component of Red Hat Fuse 7; netty-codec-http as a component of Red Hat JBoss Enterprise Application Platform 7; netty-codec-http as a component of Red Hat JBoss Enterprise Application Platform 8; netty-codec-http as a component of Red Hat JBoss Enterprise Application Platform Expansion Pack; rhoai/odh-modelmesh-rhel9 as a component of Red Hat OpenShift AI (RHOAI); rhoai/odh-openvino-model-server-rhel9 as a component of Red Hat OpenShift AI (RHOAI); and 15 more · Fixed: Red Hat build of Quarkus 3.27.4.SP1; Red Hat build of Quarkus 3.33.2.SP1
Affected versionsThe structured affected or fixed version information changed.
Before
>= 4.2.0.Final, < 4.2.15.Final; < 4.1.135.Final · Fixed: No fixed version is explicitly recorded in the structured CVE data.
After
>= 4.2.0.Final, < 4.2.15.Final; < 4.1.135.Final · Fixed: 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
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.