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TI-2026-12768 Aliases CVE-2026-15157GHSA-m8rv-5g2x-5cg5

undici vulnerable to CRLF Injection via blob-like body 'type' property

Priority LOW 24CWE-93Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
Low · Low · None
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 does not validate the type property of a duck-typed blob-like request body before using it as the Content-Type header on the HTTP/1.1 dispatcher. 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, an application that passes a hand-rolled blob-like body (via request, stream, pipeline, or dispatch) whose type is derived from untrusted input allows an attacker to inject CRLF sequences and append arbitrary HTTP headers, potentially smuggling a second request past the upstream. Native Blob objects are safe because their constructor strips CRLF from the type, and fetch is unaffected because it validates headers, but ecosystem libraries that build duck-typed blob shapes from user input can reach the vulnerable path. This is the same defect class as CVE-2022-35948 and CVE-2026-1527, on a header sink that the earlier fixes did not cover. 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 0.00261 18th 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-m8rv-5g2x-5cg5
—undici (npm)7.0.0 to before 7.29.07.29.0Patch availableGHSA-m8rv-5g2x-5cg5
—undici (npm)8.0.0 to before 8.9.08.9.0Patch availableGHSA-m8rv-5g2x-5cg5
  • 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-m8rv-5g2x-5cg5
  • undici (npm) Vendor— Affected 7.0.0 to before 7.29.0 Fixed in 7.29.0 Patch available GHSA-m8rv-5g2x-5cg5
  • undici (npm) Vendor— Affected 8.0.0 to before 8.9.0 Fixed in 8.9.0 Patch available GHSA-m8rv-5g2x-5cg5

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-m8rv-5g2x-5cg5 undici (npm) Fixed in 6.28.0 Advisory →
  • Fix · GHSA-m8rv-5g2x-5cg5 undici (npm) Fixed in 7.29.0 Advisory →
  • Fix · GHSA-m8rv-5g2x-5cg5 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-2026-13930 undici vulnerable to downstream response desynchronization via retry interceptorPriority LOW 29
    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-2026-15157
  2. 2026-10-03 Alias added: GHSA-m8rv-5g2x-5cg5

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