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TI-2026-13930 Aliases CVE-2026-16728GHSA-8xcm-r25x-g524

undici vulnerable to downstream response desynchronization via retry interceptor

Priority LOW 29CWE-444Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · Low · Low
Fix status
Partial Red Hat: 1 fixed, 1 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA, GitHub and Red Hat.

Summary

undici's retry interceptor can deliver a response whose body length does not match the Content-Length header exposed to the application after a retry or resume of a partial response. In undici before 6.28.0, from 7.0.0 up to before 7.29.0, and from 8.0.0 up to before 8.9.0, a malicious or faulty upstream can return a partial response with a mismatched framing header, close the socket early, and have the retry interceptor assemble a body of a different length while the original Content-Length stays attached. Applications that use the retry interceptor and forward upstream headers and bodies downstream, such as proxies or gateways, may then emit an invalid HTTP response with a stale Content-Length, leading to downstream response desynchronization, connection hangs, or response corruption. Exploitation requires the retry interceptor enabled, an upstream returning a mismatched partial response, and a downstream forwarder that does not remove or recalculate Content-Length. The issue is fixed in undici 6.28.0, 7.29.0, and 8.9.0.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00288 21st percentileScored 2026-11-07
Fix Partial undici (undici): 6.28.0, 7.29.0, 8.9.0undici (npm): 6.28.0, 7.29.0, 8.9.0Red Hat: 2 advisoriesRed Hat: 1 fixed, 1 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

VendorProductAffected versionsFixed inStatusSource
NodeJSundicibefore 6.28.0; 7.0.0 to before 7.29.0; 8.0.0 to before 8.9.06.28.0, 7.29.0, 8.9.0Patch availableCNA
—undici (npm)before 6.28.06.28.0Patch availableGHSA-8xcm-r25x-g524
—undici (npm)7.0.0 to before 7.29.07.29.0Patch availableGHSA-8xcm-r25x-g524
—undici (npm)8.0.0 to before 8.9.08.9.0Patch availableGHSA-8xcm-r25x-g524
  • undici VendorNodeJS Affected before 6.28.0; 7.0.0 to before 7.29.0; 8.0.0 to before 8.9.0 Fixed in 6.28.0, 7.29.0, 8.9.0 Patch available CNA
  • undici (npm) Vendor— Affected before 6.28.0 Fixed in 6.28.0 Patch available GHSA-8xcm-r25x-g524
  • undici (npm) Vendor— Affected 7.0.0 to before 7.29.0 Fixed in 7.29.0 Patch available GHSA-8xcm-r25x-g524
  • undici (npm) Vendor— Affected 8.0.0 to before 8.9.0 Fixed in 8.9.0 Patch available GHSA-8xcm-r25x-g524

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:nodejs:undici:*:*:*:*:*:node.js:*:*before 6.28.0; 7.0.0 to before 7.29.0; 8.0.0 to before 8.9.0VulnerableNodeJS
  • cpe:2.3:a:nodejs:undici:*:*:*:*:*:node.js:*:* Versions before 6.28.0; 7.0.0 to before 7.29.0; 8.0.0 to before 8.9.0 Vulnerable ·NodeJS

Remediation

  • Fix · CNA undici (undici) Fixed in 6.28.0, 7.29.0, 8.9.0
  • Fix · GHSA-8xcm-r25x-g524 undici (npm) Fixed in 6.28.0 Advisory →
  • Fix · GHSA-8xcm-r25x-g524 undici (npm) Fixed in 7.29.0 Advisory →
  • Fix · GHSA-8xcm-r25x-g524 undici (npm) Fixed in 8.9.0 Advisory →

Red Hat 2 advisories

  • RHSA-2026:48537 Released 2026-07-30 · Red Hat rating Important
    Red Hat Hardened Images RPMs bug fix and enhancement update
    • Red Hat Hardened Images nodejs24-1:24.18.1-0.1.hum1@aarch64, nodejs24-1:24.18.1-0.1.hum1@src, nodejs24-1:24.18.1-0.1.hum1@x86_64 +14
  • RHSA-2026:48273 Released 2026-07-29 · Red Hat rating Important
    Red Hat Hardened Images RPMs bug fix and enhancement update
    • Red Hat Hardened Images nodejs26-1:26.5.1-1.5.hum1@aarch64, nodejs26-1:26.5.1-1.5.hum1@src, nodejs26-1:26.5.1-1.5.hum1@x86_64 +14

Fixed in the same release

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

  • Release ·

    undici 6.28.0, 7.29.0, 8.9.0

    3 records Highest priority Priority LOW 3 LOW

    Other records, highest priority first

    • TI-2026-13931 undici vulnerable to cookie attribute injection via unsanitized domain and unparsed setCookie fieldsPriority LOW 29
    • TI-2026-12768 undici vulnerable to CRLF Injection via blob-like body 'type' propertyPriority LOW 24
    Show all 3 records →

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Hardened ImagesAffectedNo fix planned: Will not fix
Red Hat Hardened ImagesFixed RHSA-2026:48273, RHSA-2026:48537
Not affected: 1 product
  • Red Hat Hardened Images

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-16728
  2. 2026-10-03 Alias added: GHSA-8xcm-r25x-g524

References

Advisory 3

Other 11

  • 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