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Fencer Vulns
medium 6.5

CVE-2026-59903 json

Netty: Cache Poisoning and Information Disclosure via CORS Vary Header Overwrite

published 2026-08-17 2 mo ago modified 2026-09-23 47 d ago also EUVD-2026-60318 , GHSA-8c42-7qj2-3j46

cvss
6.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.3%
EPSS 0.3% chance of exploitation in 30 days, percentile 25%
public exploits
0
none known

Summary

Netty is an asynchronous, event-driven network application framework. Prior to 4.1.137.Final and 4.2.17.Final, io.netty.handler.codec.http.cors.CorsHandler setVaryHeader replaces application Vary headers such as Authorization or Cookie with Origin, allowing a caching proxy or CDN to reuse authenticated responses across users and disclose sensitive information. This issue is fixed in versions 4.1.137.Final and 4.2.17.Final.

Patch / fix

  • maven io.netty:netty-codec-http 4.1.137.Final, 4.2.17.Final
  • io.netty netty-codec-http 4.1.137.Final, 4.2.17.Final
  • netty netty 4.1.137.Final, 4.2.17.Final
  • netty-tcnative SLES for SAP 15 SP6, SLES for SAP 15 SP5, SLES for SAP 15 SP4 +8 more 2.0.84-150200.3.51.1
  • netty SLE Module for Package Hub 15 SP7 4.1.138-150200.4.56.1

suse advisories SUSE-SU-2026:4391-1

  • netty openSUSE Tumbleweed 4.1.138-1.1

opensuse advisories openSUSE-SU-2026:11882-1

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-59903 updated cvss 6.5

io.netty/netty: Netty: Information disclosure via CORS Vary header overwrite

  • Red Hat Exploit Intelligence exploit-intelligence/agent-client-rhel9 Red Hat OpenShift Serverless openshift-serverless-1/kn-ekb-receiver-rhel9 Red Hat AMQ Broker 7 netty-codec, netty-buffer, netty-common, netty-handler, netty-resolver, netty-transport, +15 more Red Hat build of Apache Camel 4 for Quarkus 3 netty-codec, netty-buffer, netty-common, netty-handler, netty-resolver, netty-codec-dns, +9 more Red Hat build of Apache Camel for Spring Boot 4 netty-all, netty-bom, netty-codec, netty-buffer, netty-common, netty-parent, +26 more Red Hat build of Apicurio Registry 3 netty-codec, netty-buffer, netty-common, netty-handler, netty-resolver, netty-codec-dns, +9 more
    +8 more products
    Red Hat build of Debezium 3 netty-codec, netty-buffer, netty-common, netty-handler, netty-resolver, netty-codec-dns, +10 more Red Hat build of Quarkus netty-codec, netty-buffer, netty-common, netty-handler, netty-resolver, netty-codec-dns, +8 more Red Hat Ceph Storage 6 ceph, cephadm, librbd1, librgw2, rbd-nbd, ceph-mib, +16 more Red Hat Ceph Storage 7 ceph, cephadm, librbd1, librgw2, rbd-nbd, ceph-mib, +16 more Red Hat Ceph Storage 8 ceph, cephadm, liborc1, librbd1, librgw2, rbd-nbd, +18 more Red Hat Ceph Storage 9 ceph, liborc, cephadm, liborc2, librbd1, librgw2, +21 more Red Hat Data Grid 8 netty-codec, netty-buffer, netty-common, netty-handler, netty-resolver, netty-codec-dns, +7 more Red Hat Enterprise Linux AI (RHEL AI) 3 bazel6, bazel7, bazel8
    affected: workaround, no fix available
  • Red Hat JBoss Enterprise Application Platform 7 netty-codec, netty-buffer, netty-common, netty-handler, netty-resolver, netty-codec-dns, +21 more
    affected: workaround, no fix planned “Will not fix”
  • Red Hat JBoss Enterprise Application Platform Expansion Pack netty-buffer, netty-codec-http2 Red Hat OpenShift AI (RHOAI) rhoai/odh-modelmesh-rhel9, rhoai/odh-spark-operator-rhel9, rhoai/odh-trustyai-service-rhel9 Red Hat OpenShift Dev Spaces devspaces/server-rhel9
    affected: workaround, no fix available
  • Red Hat Single Sign-On 7 netty, netty-codec, netty-buffer, netty-common, netty-handler, netty-resolver, +24 more
    affected: workaround, no fix planned “Will not fix”
  • Red Hat Build of Apache Camel 3.33.3.SP1 netty-codec-http 4.1.137.Final-redhat-00001
    fixed: vendor fix RHSA-2026:63302
  • Red Hat build of Keycloak 26.4 rhbk/keycloak-rhel9 26.4-29, rhbk/keycloak-rhel9-operator 26.4-30, rhbk/keycloak-operator-bundle 26.4.17-2
    fixed: vendor fix RHSA-2026:95760
  • Red Hat build of Keycloak 26.4.17
    fixed: vendor fix RHSA-2026:95759
  • Red Hat build of Keycloak 26.6 rhbk/keycloak-rhel9 26.6-24, rhbk/keycloak-rhel9-operator 26.6-24, rhbk/keycloak-operator-bundle 26.6.8-2
    fixed: vendor fix RHSA-2026:95762
show 9 more
  • Red Hat build of Keycloak 26.6.8
    fixed: vendor fix RHSA-2026:95761
  • Red Hat build of Quarkus 3.27.5.SP1 netty-codec-http 4.1.137.Final-redhat-00001
    fixed: vendor fix RHSA-2026:62515
  • Red Hat build of Quarkus 3.33.3.SP1 netty-codec-http 4.1.137.Final-redhat-00001
    fixed: vendor fix RHSA-2026:62555
  • Red Hat JBoss EAP 8.1 for RHEL 8 eap8-netty 4.1.138-1.Final_redhat_00001.1.el8eap, eap8-resteasy 6.2.19-1.Final_redhat_00002.1.el8eap, eap8-netty-codec 4.1.138-1.Final_redhat_00001.1.el8eap, eap8-resteasy-cdi 6.2.19-1.Final_redhat_00002.1.el8eap, eap8-netty-buffer 4.1.138-1.Final_redhat_00001.1.el8eap, eap8-netty-common 4.1.138-1.Final_redhat_00001.1.el8eap, +25 more
    fixed: vendor fix RHSA-2026:92057
  • Red Hat JBoss EAP 8.1 for RHEL 9 eap8-netty 4.1.138-1.Final_redhat_00001.1.el9eap, eap8-resteasy 6.2.19-1.Final_redhat_00002.1.el9eap, eap8-netty-codec 4.1.138-1.Final_redhat_00001.1.el9eap, eap8-resteasy-cdi 6.2.19-1.Final_redhat_00002.1.el9eap, eap8-netty-buffer 4.1.138-1.Final_redhat_00001.1.el9eap, eap8-netty-common 4.1.138-1.Final_redhat_00001.1.el9eap, +25 more
    fixed: vendor fix RHSA-2026:92056
  • Red Hat JBoss EAP 8.1 for RHEL 10 eap8-netty 4.1.138-1.Final_redhat_00001.1.el10eap, eap8-resteasy 6.2.19-1.Final_redhat_00002.1.el10eap, eap8-netty-codec 4.1.138-1.Final_redhat_00001.1.el10eap, eap8-resteasy-cdi 6.2.19-1.Final_redhat_00002.1.el10eap, eap8-netty-buffer 4.1.138-1.Final_redhat_00001.1.el10eap, eap8-netty-common 4.1.138-1.Final_redhat_00001.1.el10eap, +25 more
    fixed: vendor fix RHSA-2026:92059
  • Red Hat JBoss Enterprise Application Platform 8.1
    fixed: vendor fix RHSA-2026:95221
  • Red Hat AMQ Broker 7 netty-codec-http Red Hat Build of Apache Camel 3.33.3.SP1 jimfs 1.1, jna 5.8.0, bcel 6.7.0, gax 2.74.1, icu4j 78.2, joni 2.2.6, +1618 more Red Hat build of Quarkus 3.27.5.SP1 jna 5.8.0, db2 1.21.4, h2 2.3.230, y18n 5.0.8, cliui 8.0.1, guice 5.1.0, +1009 more Red Hat build of Quarkus 3.33.3.SP1 jna 5.8.0, h2 2.4.240, y18n 5.0.8, cliui 8.0.1, guice 5.1.0, wasm 2.15.3, +1018 more Red Hat Enterprise Linux 8 resteasy, resteasy-javadoc Red Hat Enterprise Linux 9 resteasy, pki-resteasy-core, pki-resteasy-client, pki-resteasy-jackson2-provider, pki-resteasy-servlet-initializer
    +3 more products
    Red Hat JBoss EAP 8.1 for RHEL 8 eap8-jaxb 4.0.8-2.redhat_00001.1.el8eap, eap8-txw2 4.0.8-2.redhat_00001.1.el8eap, eap8-xsom 4.0.8-2.redhat_00001.1.el8eap, eap8-rngom 4.0.8-2.redhat_00001.1.el8eap, eap8-log4j 2.25.5-1.redhat_00001.1.el8eap, eap8-jaxb-jxc 4.0.8-2.redhat_00001.1.el8eap, +60 more Red Hat JBoss EAP 8.1 for RHEL 9 eap8-jaxb 4.0.8-2.redhat_00001.1.el9eap, eap8-txw2 4.0.8-2.redhat_00001.1.el9eap, eap8-xsom 4.0.8-2.redhat_00001.1.el9eap, eap8-rngom 4.0.8-2.redhat_00001.1.el9eap, eap8-log4j 2.25.5-1.redhat_00001.1.el9eap, eap8-jaxb-jxc 4.0.8-2.redhat_00001.1.el9eap, +60 more Red Hat JBoss EAP 8.1 for RHEL 10 eap8-jaxb 4.0.8-2.redhat_00001.1.el10eap, eap8-txw2 4.0.8-2.redhat_00001.1.el10eap, eap8-xsom 4.0.8-2.redhat_00001.1.el10eap, eap8-rngom 4.0.8-2.redhat_00001.1.el10eap, eap8-log4j 2.25.5-1.redhat_00001.1.el10eap, eap8-jaxb-jxc 4.0.8-2.redhat_00001.1.el10eap, +59 more
    not affected: vulnerable code not present
  • Red Hat Offline Knowledge Portal offline-knowledge-portal/rhokp-rhel9
    not affected: component not present

1 more not affected in the full advisory

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
2 mo ago

Exploit prediction

0.32% chance of exploitation in the next 30 days, higher than 25% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 6.5 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N
GitHub 3.1 6.5 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N
NVD 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Affected packages

ecosystem package affected fixed in
maven io.netty:netty-codec-http
>=4.2.0.Final, <4.2.17.Final
<4.1.137.Final
4.2.17.Final
4.1.137.Final

Affected products

  • netty netty

Classification

Weakness
  • CWE-524 Use of Cache Containing Sensitive Information

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.