undici vulnerable to response truncation via oversized chunked responses in the dump interceptor
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · Low · None
- Fix status
- Partial Red Hat: 1 fixed, 17 without a fix
Attack profile from CVSS 3.1 · NVD. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-248.
Summary
undici's dump interceptor reads and discards a response body up to a configurable maximum size. When a response declares a Content-Length that exceeds the maximum, the interceptor aborts cleanly, but when a response has no Content-Length and is chunked, the interceptor instead signals completion early once the accumulated size reaches the maximum, without pausing or aborting the request. Because the underlying parser keeps delivering body bytes, a second completion signal fires and trips an internal assertion, which aborts the request and tears down the connection. The application is left observing a misleading successful status with an empty or truncated body while the connection has actually been disconnected. This affects undici versions from 7.1.0 up to 7.29.1 and from 8.0.0 up to 8.10.2. Users should upgrade to undici 7.29.1 or 8.10.2.
Why it matters now
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 | 7.1.0 to before 7.29.1; 8.0.0 to before 8.10.2 | 7.29.1, 8.10.2 | Patch available | CNA |
| — | undici (npm) | 7.1.0 to before 7.29.1 | 7.29.1 | Patch available | GHSA-2gqq-gqf2-x968 |
| — | undici (npm) | 8.0.0 to before 8.10.2 | 8.10.2 | Patch available | GHSA-2gqq-gqf2-x968 |
- undici VendorNodeJS Affected 7.1.0 to before 7.29.1; 8.0.0 to before 8.10.2 Fixed in 7.29.1, 8.10.2 Patch available CNA
- undici (npm) Vendor— Affected 7.1.0 to before 7.29.1 Fixed in 7.29.1 Patch available GHSA-2gqq-gqf2-x968
- undici (npm) Vendor— Affected 8.0.0 to before 8.10.2 Fixed in 8.10.2 Patch available GHSA-2gqq-gqf2-x968
Remediation
- Fix · CNA undici (undici) Fixed in 7.29.1, 8.10.2
- Fix · GHSA-2gqq-gqf2-x968 undici (npm) Fixed in 7.29.1 Advisory →
- Fix · GHSA-2gqq-gqf2-x968 undici (npm) Fixed in 8.10.2 Advisory →
Red Hat 3 advisories
- RHSA-2026:66008 Released 2026-09-09 · Red Hat rating ImportantRed Hat Hardened Images RPMs bug fix and enhancement update
- Red Hat Hardened Images grafana12.4-12.4.10-0.2.hum1@aarch64, grafana12.4-12.4.10-0.2.hum1@src, grafana12.4-12.4.10-0.2.hum1@x86_64
- RHSA-2026:54438 Released 2026-08-12 · Red Hat rating ImportantRed Hat Hardened Images RPMs bug fix and enhancement update
- Red Hat Hardened Images nodejs24-1:24.18.1-0.2.2.hum1@aarch64, nodejs24-1:24.18.1-0.2.2.hum1@src, nodejs24-1:24.18.1-0.2.2.hum1@x86_64 +14
- RHSA-2026:54389 Released 2026-08-12 · Red Hat rating ImportantRed Hat Hardened Images RPMs Security Update
- Red Hat Hardened Images nodejs26-1:26.7.0-1.5.2.hum1@aarch64, nodejs26-1:26.7.0-1.5.2.hum1@src, nodejs26-1:26.7.0-1.5.2.hum1@x86_64 +16
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Release ·
undici 7.29.1, 8.10.2
7 records Highest priority Priority MEDIUM 1 MEDIUM, 6 LOW
Other records, highest priority first
- TI-2026-58384 undici vulnerable to TLS certificate validation bypass via dropped connect options in BalancedPoolPriority MEDIUM 40
- TI-2026-58374 undici vulnerable to cross-user cookie disclosure via Set-Cookie caching in shared cachesPriority LOW 35
- TI-2026-58409 undici vulnerable to Denial of Service via WebSocketStream unclean closePriority LOW 33
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Exploit Intelligence | Affected | No fix planned: Out of support scope |
| OpenShift Pipelines | Affected | No fix yet: Fix deferred |
| Red Hat AMQ Broker 7 | Affected | No fix yet: Fix deferred |
| Red Hat Ansible Automation Platform 2 | 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 10 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 8 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 9 | Affected | No fix yet: Fix deferred |
| Red Hat Hardened Images | Affected | No fix planned: Will not fix |
| 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 Dev Spaces | Affected | No fix yet: Fix deferred |
| Red Hat Openshift Data Foundation 4 | Affected | No fix yet: Fix deferred |
| Red Hat Trusted Artifact Signer | Affected | No fix planned: Out of support scope |
| Secrets Management Console for Red Hat OpenShift | Affected | No fix planned: Out of support scope |
| Self-service automation portal 2 | Affected | No fix yet: Fix deferred |
| Red Hat Hardened Images | Fixed | RHSA-2026:54389, RHSA-2026:54438, RHSA-2026:66008 |
Not affected: 1 product
- Red Hat Hardened Images
Timeline
- 2026-10-02 Threatist record created from CVE-2026-84947
- 2026-10-03 Alias added: GHSA-2gqq-gqf2-x968
- 2026-10-27 Affected versions changed · Red Hat
References
Advisory 3
Other 5
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-2026-84947 · CVE Program
- CVE-2026-84947 · NVD
- FIRST EPSS
- GHSA-2gqq-gqf2-x968 · GitHub Advisory Database · CC BY 4.0
- CVE-2026-84947 · 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