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Fencer Intel
high 7.4

CVE-2026-109829 json

undici vulnerable to cache poisoning and cross-user disclosure via cross-origin redirects

published 25d ago modified 13d ago also GHSA-4w7w-5xrc-9h26 , EUVD-2026-102309

cvss
7.4
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.1%
EPSS 0.1% chance of exploitation in 30 days, percentile 4%
public exploits
0
none known

Summary

undici is an HTTP client library for Node.js. In versions 7.0.0 through 7.30.0 and 8.0.0 through 8.12.1, when an originless Agent composes the redirect and cache interceptors in that order with a shared cache store, the cache builds its key from the original request URL before the redirect handler changes the origin, so a response produced after a cross-origin redirect is stored under the original key. An attacker who controls the target of a redirect from a trusted URL can have their response cached under that trusted URL and served to later callers, allowing persistent cache poisoning, and the same key confusion lets a private, non-stored redirect response to a user-specific resource be stored under the original URL and served to a later unauthenticated caller, disclosing private data. Applications are affected only when an originless Agent, a shared cache store, and the redirect-then-cache composition are all used. The issue is fixed in undici 7.30.1 and 8.12.2, which verify the producing origin still matches the cache key and preserve each redirect hop's cache-control policy before storing, and users should upgrade to one of those versions or later. As a workaround, compose the cache interceptor before the redirect interceptor, use per-origin dispatchers and cache stores, or disable shared caching on redirect-capable requests.

Patch / fix

  • npm undici 7.30.1, 8.12.2
  • undici undici 7.30.1, 8.12.2
  • node-undici Debian 14 8.12.2+dfsg+~cs3.2.3-1

debian advisories DEBIAN-CVE-2026-109829

  • nodejs24 hummingbird 1 24.21.0-1.5.hum1
  • nodejs24-bin hummingbird 1 24.21.0-1.5.hum1
  • nodejs24-npm hummingbird 1 11.19.0-1.24.21.0.1.5.hum1
  • nodejs24-libs hummingbird 1 24.21.0-1.5.hum1
  • nodejs24-npm-bin hummingbird 1 24.21.0-1.5.hum1
  • nodejs24-full-i18n hummingbird 1 24.21.0-1.5.hum1
  • nodejs26 hummingbird 1 26.11.1-0.4.hum1
  • nodejs26-bin hummingbird 1 26.11.1-0.4.hum1

red hat advisories RHSA-2026:84706RHSA-2026:84657

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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-2026-109829 updated cvss 7.4

undici: undici: Cache poisoning and information disclosure via improper cross-origin redirect caching

  • Red Hat Exploit Intelligence exploit-intelligence/vulnerability-analysis-rhel9 Red Hat AMQ Broker 7 amq-broker-maven-repository.zip 7.14.1.CR3 Red Hat Build of Podman Desktop rh-podman-desktop a4ea1f988eb28bc86ab3516bba3a4973b252a17e Red Hat Developer Hub 1 rhdh/rhdh-hub-rhel9, rhdh/red-hat-developer-hub-backstage-plugin-lightspeed-backend, rhdh/red-hat-developer-hub-backstage-plugin-orchestrator-backend, rhdh/red-hat-developer-hub-backstage-plugin-orchestrator-backend-module-loki, rhdh/red-hat-developer-hub-backstage-plugin-scaffolder-backend-module-orchestrator Red Hat Enterprise Linux 8 ubi8/s2i-base Red Hat Enterprise Linux 9 npm, nodejs, nodejs-libs, nodejs-full-i18n
    +1 more products
    Red Hat Enterprise Linux 10 nodejs26
    affected: no fix available
  • Red Hat Hardened Images nodejs25 25.9.0-1.7.hum1
    affected: no fix planned “Will not fix”
  • Red Hat OpenShift AI (RHOAI) rhoai/odh-mlflow-rhel9, rhoai/odh-core-bff-rhel9, rhoai/odh-dashboard-operator-rhel9, rhoai/odh-mod-arch-agent-ops-rhel9, rhoai/odh-workbench-codeserver-datascience-cpu-py312-rhel9 Red Hat OpenShift Container Platform 4 wasmedge, wasmedge-rt, openshift4/ose-monitoring-plugin-rhel9 Red Hat OpenShift Container Platform 5 openshift5/ose-monitoring-plugin-rhel9 Red Hat Openshift Data Foundation 4 odf4/odf-console-rhel9, odf4/ocs-client-console-rhel9, odf4/odf-multicluster-console-rhel9 Red Hat OpenShift Dev Spaces devspaces/code-rhel9, devspaces/openvsx-rhel9, devspaces/dashboard-rhel9, devspaces/pluginregistry-rhel9
    affected: no fix available
  • Red Hat Secrets Management Console for Red Hat OpenShift external-secrets-management/console-plugin-rhel9
    affected: no fix planned “Will not fix”
  • Red Hat Self-service automation portal 2 ansible-automation-platform/automation-portal, ansible-automation-platform/bootc-automation-portal-rhel9
    affected: no fix available
  • Red Hat Cluster Observability Operator 1.5 cluster-observability-operator/monitoring-console-plugin-rhel9 1793663585, cluster-observability-operator/monitoring-console-plugin-rhel9 1793827684, cluster-observability-operator/logging-console-plugin-pf4-rhel9 1793660952, cluster-observability-operator/logging-console-plugin-pf4-rhel9 1793824934, cluster-observability-operator/monitoring-console-plugin-pf5-rhel9 1793662327, cluster-observability-operator/monitoring-console-plugin-pf5-rhel9 1793827768, +10 more
    fixed: vendor fix RHSA-2026:95591
  • Red Hat Enterprise Linux AppStream (v. 10) nodejs 22.23.4-1.el10_2, nodejs22 22.23.4-1.el10_2, nodejs24 24.22.1-3.el10_2, nodejs-libs 22.23.4-1.el10_2, nodejs24-libs 24.22.1-3.el10_2, nodejs-full-i18n 22.23.4-1.el10_2, +3 more
    fixed: vendor fix RHSA-2026:96094
  • Red Hat Hardened Images nodejs24 24.21.0-1.5.hum1, nodejs26 26.11.1-0.4.hum1, nodejs24-bin 24.21.0-1.5.hum1, nodejs26-bin 26.11.1-0.4.hum1, nodejs24-libs 24.21.0-1.5.hum1, nodejs26-libs 26.11.1-0.4.hum1, +6 more
    fixed: vendor fix RHSA-2026:84706
show 5 more
  • Red Hat OpenShift AI 3.4 rhoai/odh-dashboard-rhel9 1793001801, rhoai/odh-mod-arch-maas-rhel9 1793001859, rhoai/odh-mod-arch-automl-rhel9 1793001841, rhoai/odh-mod-arch-gen-ai-rhel9 1793001896, rhoai/odh-mod-arch-mlflow-rhel9 1793001851, rhoai/odh-mod-arch-autorag-rhel9 1793001850, +2 more
    fixed: vendor fix RHSA-2026:92510
  • Red Hat Trusted Artifact Signer 1.5 rhtas/rhtas-console-ui-rhel9 1793114810
    fixed: vendor fix RHSA-2026:95124
  • Red Hat Cluster Observability Operator 1.5 cluster-observability-operator/perses-rhel9 1793661985, cluster-observability-operator/perses-rhel9 1793825744, cluster-observability-operator/thanos-rhel9 1793660568, cluster-observability-operator/thanos-rhel9 1793821585, cluster-observability-operator/korrel8r-rhel9 1793661297, cluster-observability-operator/korrel8r-rhel9 1793822079, +28 more
    not affected: vulnerable code not present
  • Red Hat Cryostat 4 cryostat/cryostat-openshift-console-plugin-rhel9
    not affected: component not present
  • Red Hat AMQ Broker 7 amq-broker-bin.zip 7.14.1.CR3 Red Hat Ansible Automation Platform 2 automation-platform-ui 2.6.15-1.el9ap Red Hat Enterprise Linux 8 npm, nodejs, nodejs-libs, nodejs-nodemon, ubi8/nodejs-24, nodejs-full-i18n, +3 more Red Hat Enterprise Linux 9 npm, nodejs, nodejs-libs, ubi9/nodejs-24, nodejs-full-i18n, ubi9/nodejs-24-minimal Red Hat Enterprise Linux 10 grafana 12.4.3-2.el10 Red Hat Hardened Images grafana12.4 12.4.12-0.4.hum1
    +3 more products
    Red Hat OpenShift AI 3.4 rhoai/odh-cli-rhel9 1792722177, rhoai/rhai-cli-rhel9 1792722177, rhoai/odh-automl-rhel9 1792697253, rhoai/odh-mlflow-rhel9 1793002327, rhoai/odh-autorag-rhel9 1793265800, rhoai/odh-trainer-rhel9 1792817113, +92 more Red Hat Openshift Data Foundation 4 odf4/mcg-core-rhel9 Red Hat Trusted Artifact Signer 1.5 rhtas/rhtas-console-rhel9 1793108442
    not affected: vulnerable code not present

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
total
Assessed
24d ago

Exploit prediction

0.15% chance of exploitation in the next 30 days, higher than 4% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CNA 3.1 7.4 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
NVD 3.1 9.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
GitHub 3.1 7.4 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

Affected packages

ecosystem package affected fixed in
npm undici
>=7.0.0, <7.30.1
>=8.0.0, <8.12.2
7.30.1
8.12.2

Affected products

  • undici undici

Classification

Weakness
  • CWE-346 Origin Validation Error
  • CWE-524 Use of Cache Containing Sensitive Information

References

Sources

Fencer Intel 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.