Read the docs
TI-2026-74886 Aliases CVE-2026-109383GHSA-2m5v-pch6-74hx

Certificate validation bypass in undici Agent drops custom TLS checks

Priority MEDIUM 40CWE-295Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Spoofing
Confidentiality · integrity · availability
High · High · None
Fix status
Partial Red Hat: 4 fixed, 15 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-295.

Summary

undici versions from 4.0.0 before 6.29.1, from 7.0.0 before 7.30.1 and from 8.0.0 before 8.12.2 are affected. The Agent dispatcher's JSON deep clone silently drops function-valued tls options such as checkServerIdentity, which causes improper certificate validation (CWE-295). A remote TLS peer with a certificate that passes Node's default checks but that a custom checkServerIdentity would reject is silently accepted, and only applications that pass such callbacks for certificate or public-key pinning are at risk.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

Description from the CNA

undici is an HTTP client library for Node.js. In versions 4.0.0 through 6.29.0, 7.0.0 through 7.30.0, and 8.0.0 through 8.12.1, its Agent dispatcher passes its constructor options through a JSON-based deep clone before forwarding them to each per-origin pool, and because JSON cannot represent functions, a caller-supplied tls option containing a checkServerIdentity callback is silently dropped before it reaches the TLS layer. As a result, a TLS peer whose certificate a custom checkServerIdentity was written to reject, but which passes Node's default hostname and chain checks, is silently accepted. Because Agent is the default dispatcher behind request, fetch, and setGlobalDispatcher, this affects the path most applications use, and EnvHttpProxyAgent is affected on its direct and no-proxy routes as well, while only applications that pass a function-valued tls option such as a custom checkServerIdentity for certificate or public-key pinning are at risk. The issue is fixed in undici 6.29.1, 7.30.1, and 8.12.2, which preserve the tls option outside the JSON clone so custom verification callbacks are forwarded unchanged, and users should upgrade to one of those versions or later. As a workaround, pass the TLS options through connect instead of tls, or for proxied destinations use requestTls and proxyTls.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00184 8th percentileScored 2026-11-07
Fix Partial undici (undici): 6.29.1, 7.30.1, 8.12.2undici (npm): 6.29.1, 7.30.1, 8.12.2Red Hat: 7 advisoriesRed Hat: 4 fixed, 15 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
NodeJSundici4.0.0 to before 6.29.1; 7.0.0 to before 7.30.1; 8.0.0 to before 8.12.26.29.1, 7.30.1, 8.12.2Patch availableCNA
—undici (npm)4.0.0 to before 6.29.16.29.1Patch availableGHSA-2m5v-pch6-74hx
—undici (npm)7.0.0 to before 7.30.17.30.1Patch availableGHSA-2m5v-pch6-74hx
—undici (npm)8.0.0 to before 8.12.28.12.2Patch availableGHSA-2m5v-pch6-74hx
  • undici VendorNodeJS Affected 4.0.0 to before 6.29.1; 7.0.0 to before 7.30.1; 8.0.0 to before 8.12.2 Fixed in 6.29.1, 7.30.1, 8.12.2 Patch available CNA
  • undici (npm) Vendor— Affected 4.0.0 to before 6.29.1 Fixed in 6.29.1 Patch available GHSA-2m5v-pch6-74hx
  • undici (npm) Vendor— Affected 7.0.0 to before 7.30.1 Fixed in 7.30.1 Patch available GHSA-2m5v-pch6-74hx
  • undici (npm) Vendor— Affected 8.0.0 to before 8.12.2 Fixed in 8.12.2 Patch available GHSA-2m5v-pch6-74hx

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:nodejs:undici:*:*:*:*:*:node.js:*:*4.0.0 to before 6.29.1; 7.0.0 to before 7.30.1; 8.0.0 to before 8.12.2VulnerableNodeJS
  • cpe:2.3:a:nodejs:undici:*:*:*:*:*:node.js:*:* Versions 4.0.0 to before 6.29.1; 7.0.0 to before 7.30.1; 8.0.0 to before 8.12.2 Vulnerable ·NodeJS

Remediation

Upgrade undici to 6.29.1, 7.30.1 or 8.12.2 or later. Red Hat advisories RHSA-2026:95591, RHSA-2026:95124, RHSA-2026:95081, RHSA-2026:92510, RHSA-2026:87703, RHSA-2026:84706 and RHSA-2026:84657 cover the fix. The sources list no fixed version for Red Hat Enterprise Linux 8, 9 and 10, and no fix planned for Secrets Management Console for Red Hat OpenShift. As a workaround, pass TLS options through connect instead of tls.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

  • Fix · CNA undici (undici) Fixed in 6.29.1, 7.30.1, 8.12.2
  • Fix · GHSA-2m5v-pch6-74hx undici (npm) Fixed in 6.29.1 Advisory →
  • Fix · GHSA-2m5v-pch6-74hx undici (npm) Fixed in 7.30.1 Advisory →
  • Fix · GHSA-2m5v-pch6-74hx undici (npm) Fixed in 8.12.2 Advisory →

Red Hat 7 advisories

  • RHSA-2026:95591 Released 2026-11-05 · Red Hat rating Important
    Cluster Observability Operator - 1.5
    • Cluster Observability Operator 1.5 registry.redhat.io/cluster-observability-operator/alertmanager-rhel9, registry.redhat.io/cluster-observability-operator/cluster-observability-rhel9-operator, registry.redhat.io/cluster-observability-operator/distributed-tracing-console-plugin-pf4-rhel9 +16
  • RHSA-2026:95124 Released 2026-11-04 · Red Hat rating Important
    RHTAS 1.5.1 - Red Hat Trusted Artifact Signer Release
    • Red Hat Trusted Artifact Signer 1.5 registry.redhat.io/rhtas/rhtas-console-rhel9, registry.redhat.io/rhtas/rhtas-console-ui-rhel9
  • RHSA-2026:95081 Released 2026-11-04 · Red Hat rating Important
    Cluster Observability Operator - 1.5
    • Cluster Observability Operator 1.5 registry.redhat.io/cluster-observability-operator/alertmanager-rhel9, registry.redhat.io/cluster-observability-operator/cluster-observability-rhel9-operator, registry.redhat.io/cluster-observability-operator/distributed-tracing-console-plugin-pf4-rhel9 +16
Show 4 more Red Hat advisories
  • RHSA-2026:92510 Released 2026-10-29 · Red Hat rating Critical
    RHOAI 3.4.6 - Red Hat OpenShift AI
    • Red Hat OpenShift AI 3.4 registry.redhat.io/rhoai/odh-built-in-detector-rhel9, registry.redhat.io/rhoai/odh-cli-rhel9, registry.redhat.io/rhoai/odh-dashboard-rhel9 +47
  • RHSA-2026:87703 Released 2026-10-22 · Red Hat rating Important
    Red Hat Hardened Images RPMs bug fix and enhancement update
    • Red Hat Hardened Images nodejs26-1:26.12.1-0.1.hum1@aarch64, nodejs26-1:26.12.1-0.1.hum1@s390x, nodejs26-1:26.12.1-0.1.hum1@src +22
  • RHSA-2026:84706 Released 2026-10-19 · Red Hat rating Important
    Red Hat Hardened Images RPMs Security Update
    • Red Hat Hardened Images nodejs24-24.21.0-1.5.hum1@aarch64, nodejs24-24.21.0-1.5.hum1@s390x, nodejs24-24.21.0-1.5.hum1@src +25
  • RHSA-2026:84657 Released 2026-10-19 · Red Hat rating Important
    Red Hat Hardened Images RPMs Security Update
    • Red Hat Hardened Images nodejs26-26.11.1-0.4.hum1@aarch64, nodejs26-26.11.1-0.4.hum1@s390x, nodejs26-26.11.1-0.4.hum1@src +25

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    undici 6.29.1, 7.30.1, 8.12.2

    5 records Highest priority Priority MEDIUM 1 MEDIUM, 4 LOW

    Other records, highest priority first

    • TI-2026-74890 Unhandled error in undici fetch() crashes Node.js processPriority LOW 39
    • TI-2026-74992 Denial of service in undici via TLS renegotiationPriority LOW 38
    • TI-2026-74894 Undici WebSocket client exhausts memory via unbounded PONG bufferingPriority LOW 33
    Show all 5 records →

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Exploit IntelligenceAffectedNo fix yet
Red Hat AMQ Broker 7AffectedNo fix yet
Red Hat Build of Podman DesktopAffectedNo fix yet
Red Hat Developer Hub 1AffectedNo fix yet
Red Hat Enterprise Linux 10AffectedNo fix yet
Red Hat Enterprise Linux 8AffectedNo fix yet
Red Hat Enterprise Linux 9AffectedNo fix yet
Red Hat Hardened ImagesAffectedNo fix planned: Will not fix
Red Hat OpenShift AI (RHOAI)AffectedNo fix yet
Red Hat OpenShift Container Platform 4AffectedNo fix yet
Red Hat OpenShift Container Platform 5AffectedNo fix yet
Red Hat OpenShift Dev SpacesAffectedNo fix yet
Red Hat Openshift Data Foundation 4AffectedNo fix yet
Secrets Management Console for Red Hat OpenShiftAffectedNo fix planned: Will not fix
Self-service automation portal 2AffectedNo fix yet
Cluster Observability Operator 1.5Fixed RHSA-2026:95081, RHSA-2026:95591
Red Hat Hardened ImagesFixed RHSA-2026:84657, RHSA-2026:84706, RHSA-2026:87703
Red Hat OpenShift AI 3.4Fixed RHSA-2026:92510
Red Hat Trusted Artifact Signer 1.5Fixed RHSA-2026:95124
Not affected: 9 products
  • Cluster Observability Operator 1.5
  • Cryostat 4
  • Red Hat AMQ Broker 7
  • Red Hat Ansible Automation Platform 2
  • Red Hat Enterprise Linux 10
  • Red Hat Hardened Images
  • Red Hat OpenShift AI 3.4
  • Red Hat OpenShift Container Platform 4
  • Red Hat Trusted Artifact Signer 1.5

Timeline

  1. 2026-10-16 Threatist record created from CVE-2026-109383
  2. 2026-10-16 Priority changed: MEDIUM → LOW
  3. 2026-10-16 Affected versions changed · Red Hat
  4. 2026-10-16 CVSS score added · Red Hat
  5. 2026-10-18 CISA SSVC decision points changed
  6. 2026-10-18 Affected versions changed · Red Hat
  7. 2026-10-19 Fix available: RHSA-2026:84657 · Red Hat
  8. 2026-10-19 Fix available: RHSA-2026:84706 · Red Hat
  9. 2026-10-20 CVSS score added · NVD
  10. 2026-10-20 Priority changed: LOW → MEDIUM
  11. 2026-10-20 Fix available: Red Hat Hardened Images · Red Hat
  12. 2026-10-22 Fix available: RHSA-2026:87703 · Red Hat
  13. 2026-10-23 Affected versions changed · Red Hat
  14. 2026-10-27 Affected versions changed · Red Hat
  15. 2026-10-27 Alias added: GHSA-2m5v-pch6-74hx
  16. 2026-10-30 Fix available: RHSA-2026:92510 · Red Hat
  17. 2026-10-30 Fix available: Red Hat OpenShift AI 3.4 · Red Hat
  18. 2026-10-30 Affected versions changed · Red Hat
  19. 2026-11-03 Affected versions changed · Red Hat
  20. 2026-11-04 Fix available: RHSA-2026:95081 · Red Hat
  21. 2026-11-04 Fix available: RHSA-2026:95124 · Red Hat
  22. 2026-11-04 Fix available: Cluster Observability Operator 1.5, Red Hat Trusted Artifact Signer 1.5 · Red Hat
  23. 2026-11-06 Affected versions changed · Red Hat
  24. 2026-11-06 Fix available: RHSA-2026:95591 · Red Hat

References

Advisory 3

Other 7

  • TI-2026-01215 undici is vulnerable to Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') CVSS 3.1CRITICAL 9.8
  • TI-2022-16376 `undici.request` vulnerable to SSRF using absolute URL on `pathname` CVSS 3.1CRITICAL 9.8
  • TI-2023-09734 CRLF Injection in Nodejs ‘undici’ via host CVSS 3.1MEDIUM 6.5
  • TI-2022-13193 CRLF injection in request headers CVSS 3.1MEDIUM 6.5
  • TI-2022-16375 CRLF Injection in Nodejs ‘undici’ via Content-Type CVSS 3.1MEDIUM 5.3
  • TI-2022-13194 Uncleared cookies on cross-host/cross-origin redirect in undici CVSS 3.1MEDIUM 6.5
See all 51 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences