undici vulnerable to HTTP response queue poisoning via keep-alive socket reuse
Priority LOW 17CWE-367Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- High
- Impact type
- —
- Confidentiality · integrity · availability
- None · Low · None
- Fix status
- Partial Red Hat: 5 fixed, 12 without a fix
Attack profile from CVSS 3.1 · CNA. Fix status from CNA, GitHub and Red Hat.
Summary
Impact: Undici's HTTP/1.1 client is vulnerable to response queue poisoning on reused keep-alive sockets. An attacker-controlled upstream server can inject an unsolicited HTTP/1.1 response onto an idle socket after a request completes. When the client dispatches the next request on that socket, it associates the injected response with the new request, causing responses to be delivered to the wrong requests. This requires an attacker-controlled or compromised upstream HTTP/1.1 server and keep-alive connection reuse. Patches: Upgrade to undici v6.26.0, v7.28.0 or v8.5.0. Workarounds: Disable keep-alive connection reuse by setting keepAliveTimeout: 0 on the Client or Pool.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0022 12th percentileScored 2026-11-07
Fix Partial undici (undici): 6.26.0, 7.28.0, 8.5.0undici (npm): 6.27.0, 7.28.0, 8.5.0Red Hat: 9 advisoriesRed Hat: 5 fixed, 12 without a fix
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| NodeJS | undici | before 6.26.0; 7.0.0 to before 7.28.0; 8.0.0 to before 8.5.0 | 6.26.0, 7.28.0, 8.5.0 | Patch available | CNA |
| — | undici (npm) | before 6.27.0 | 6.27.0 | Patch available | GHSA-35p6-xmwp-9g52 |
| — | undici (npm) | 7.0.0 to before 7.28.0 | 7.28.0 | Patch available | GHSA-35p6-xmwp-9g52 |
| — | undici (npm) | 8.0.0 to before 8.5.0 | 8.5.0 | Patch available | GHSA-35p6-xmwp-9g52 |
- undici VendorNodeJS Affected before 6.26.0; 7.0.0 to before 7.28.0; 8.0.0 to before 8.5.0 Fixed in 6.26.0, 7.28.0, 8.5.0 Patch available CNA
- undici (npm) Vendor— Affected before 6.27.0 Fixed in 6.27.0 Patch available GHSA-35p6-xmwp-9g52
- undici (npm) Vendor— Affected 7.0.0 to before 7.28.0 Fixed in 7.28.0 Patch available GHSA-35p6-xmwp-9g52
- undici (npm) Vendor— Affected 8.0.0 to before 8.5.0 Fixed in 8.5.0 Patch available GHSA-35p6-xmwp-9g52
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:nodejs:undici:*:*:*:*:*:node.js:*:* | before 6.27.0; 7.0.0 to before 7.28.0; 8.0.0 to before 8.5.0 | Vulnerable | NodeJS |
- cpe:2.3:a:nodejs:undici:*:*:*:*:*:node.js:*:* Versions before 6.27.0; 7.0.0 to before 7.28.0; 8.0.0 to before 8.5.0 Vulnerable ·NodeJS
Remediation
- Fix · CNA undici (undici) Fixed in 6.26.0, 7.28.0, 8.5.0
- Fix · GHSA-35p6-xmwp-9g52 undici (npm) Fixed in 6.27.0 Advisory →
- Fix · GHSA-35p6-xmwp-9g52 undici (npm) Fixed in 7.28.0 Advisory →
- Fix · GHSA-35p6-xmwp-9g52 undici (npm) Fixed in 8.5.0 Advisory →
Red Hat 9 advisories
- RHSA-2026:56431 Released 2026-08-18 · Red Hat rating ImportantRed Hat OpenShift Data Foundation 4.18.27 security, enhancement & bug fix update
- Red Hat Openshift Data Foundation 4.18 registry.redhat.io/odf4/cephcsi-rhel9, registry.redhat.io/odf4/cephcsi-rhel9-operator, registry.redhat.io/odf4/mcg-core-rhel9 +16
- RHSA-2026:41947 Released 2026-07-20 · Red Hat rating Importantnodejs:22 security, bug fix, and enhancement update
- Red Hat Enterprise Linux AppStream (v. 8) nodejs-1:22.23.1-1.module+el8.10.0+24500+8eb51621.aarch64::nodejs:22, nodejs-1:22.23.1-1.module+el8.10.0+24500+8eb51621.ppc64le::nodejs:22, nodejs-1:22.23.1-1.module+el8.10.0+24500+8eb51621.s390x::nodejs:22 +28
- RHSA-2026:39868 Released 2026-07-15 · Red Hat rating Importantnodejs:24 security, bug fix, and enhancement update
- Red Hat Enterprise Linux AppStream (v. 8) nodejs-1:24.18.0-1.module+el8.10.0+24481+7a71fac8.aarch64::nodejs:24, nodejs-1:24.18.0-1.module+el8.10.0+24481+7a71fac8.ppc64le::nodejs:24, nodejs-1:24.18.0-1.module+el8.10.0+24481+7a71fac8.s390x::nodejs:24 +25
Show 6 more Red Hat advisories
- RHSA-2026:38236 Released 2026-07-11 · Red Hat rating ImportantRed Hat Hardened Images RPMs Security Update
- Red Hat Hardened Images nodejs24-1:24.18.0-0.3.hum1@aarch64, nodejs24-1:24.18.0-0.3.hum1@src, nodejs24-1:24.18.0-0.3.hum1@x86_64 +16
- RHSA-2026:38009 Released 2026-07-10 · Red Hat rating ImportantRed Hat Hardened Images RPMs bug fix and enhancement update
- Red Hat Hardened Images nodejs26-1:26.5.0-1.3.hum1@aarch64, nodejs26-1:26.5.0-1.3.hum1@src, nodejs26-1:26.5.0-1.3.hum1@x86_64 +14
- RHSA-2026:35892 Released 2026-07-06 · Red Hat rating Importantnodejs:22 security, bug fix, and enhancement update
- Red Hat Enterprise Linux AppStream (v. 9) nodejs-1:22.23.1-1.module+el9.8.0+24457+996af7aa.aarch64::nodejs:22, nodejs-1:22.23.1-1.module+el9.8.0+24457+996af7aa.ppc64le::nodejs:22, nodejs-1:22.23.1-1.module+el9.8.0+24457+996af7aa.s390x::nodejs:22 +28
- RHSA-2026:35891 Released 2026-07-06 · Red Hat rating Importantnodejs:24 security, bug fix, and enhancement update
- Red Hat Enterprise Linux AppStream (v. 9) nodejs-1:24.18.0-1.module+el9.8.0+24456+b244c3b4.aarch64::nodejs:24, nodejs-1:24.18.0-1.module+el9.8.0+24456+b244c3b4.ppc64le::nodejs:24, nodejs-1:24.18.0-1.module+el9.8.0+24456+b244c3b4.s390x::nodejs:24 +25
- RHSA-2026:35842 Released 2026-07-06 · Red Hat rating Importantnodejs22 security, bug fix, and enhancement update
- Red Hat Enterprise Linux AppStream (v. 10) nodejs-1:22.23.1-2.el10_2, nodejs-devel-1:22.23.1-2.el10_2, nodejs-docs-1:22.23.1-2.el10_2 +4
- RHSA-2026:35841 Released 2026-07-06 · Red Hat rating Importantnodejs24 security, bug fix, and enhancement update
- Red Hat Enterprise Linux AppStream (v. 10) nodejs24-1:24.18.0-1.el10_2, nodejs24-devel-1:24.18.0-1.el10_2, nodejs24-docs-1:24.18.0-1.el10_2 +3
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Release ·
undici 6.26.0, 7.28.0, 8.5.0
4 records Highest priority Priority MEDIUM 1 MEDIUM, 3 LOW
Other records, highest priority first
- TI-2026-10459 undici WebSocket client vulnerable to denial of service via fragment count bypassPriority MEDIUM 40
- TI-2026-08490 undici vulnerable to HTTP header injection via Set-Cookie percent-decodingPriority LOW 26
- TI-2026-09954 undici vulnerable to Set-Cookie SameSite attribute downgrade via permissive substring matchingPriority LOW 17
Vendor assessments
Red Hat
Red Hat rating: Low. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Cryostat 4 | Affected | No fix yet: Fix deferred |
| OpenShift Pipelines | Affected | No fix yet: Fix deferred |
| Red Hat AMQ Broker 7 | Affected | No fix yet: Fix deferred |
| Red Hat Build of Podman Desktop | Affected | No fix yet: Fix deferred |
| Red Hat Developer Hub 1 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 8 | Affected | No fix yet: Fix deferred |
| Red Hat Hardened Images | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift AI (RHOAI) | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift Container Platform 4 | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift Container Platform 5 | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift Dev Spaces | Affected | No fix yet: Fix deferred |
| Self-service automation portal 2 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux AppStream (v. 10) | Fixed | RHSA-2026:35841, RHSA-2026:35842 |
| Red Hat Enterprise Linux AppStream (v. 8) | Fixed | RHSA-2026:39868, RHSA-2026:41947 |
| Red Hat Enterprise Linux AppStream (v. 9) | Fixed | RHSA-2026:35891, RHSA-2026:35892 |
| Red Hat Hardened Images | Fixed | RHSA-2026:38009, RHSA-2026:38236 |
| Red Hat Openshift Data Foundation 4.18 | Fixed | RHSA-2026:56431 |
Not affected: 2 products
- Red Hat Hardened Images
- Red Hat Openshift Data Foundation 4.18
Timeline
- 2026-10-02 Threatist record created from CVE-2026-6733
- 2026-10-03 Alias added: GHSA-35p6-xmwp-9g52
- 2026-10-27 Affected versions changed · Red Hat
- 2026-11-07 Affected versions changed · Red Hat
References
Advisory 3
Other 6
- https://hackerone.com/reports/3582376
- https://github.com/nodejs/undici/commit/6ea54ef8c4051e95bb68c89d4a5c9274fe6fbb4b
- https://github.com/nodejs/undici
- https://github.com/nodejs/undici/releases/tag/v6.27.0
- https://github.com/nodejs/undici/releases/tag/v7.28.0
- https://github.com/nodejs/undici/releases/tag/v8.5.0
More NodeJS Undici vulnerabilities
- 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
Sources
- CVE-2026-6733 · CVE Program
- CVE-2026-6733 · NVD
- FIRST EPSS
- GHSA-35p6-xmwp-9g52 · GitHub Advisory Database · CC BY 4.0
- CVE-2026-6733 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences