CVE-2026-1527

MEDIUM EPSS 16.9%
Published Mar 12, 20263mo ago · Modified Jun 17, 20262w ago
4.6 CVSS 3.1
Medium
Find Similar
Published Mar 12, 2026 3mo ago
Last Modified Jun 17, 2026 2w ago

Description

ImpactWhen an application passes user-controlled input to the upgrade option of client.request(), an attacker can inject CRLF sequences (\r\n) to: * Inject arbitrary HTTP headers * Terminate the HTTP request prematurely and smuggle raw data to non-HTTP services (Redis, Memcached, Elasticsearch) The vulnerability exists because undici writes the upgrade value directly to the socket without validating for invalid header characters: // lib/dispatcher/client-h1.js:1121 if (upgrade) { header += `connection: upgrade\r\nupgrade: ${upgrade}\r\n` }

CVSS Details

Base Score
4.6
Exploitability
2.1
Impact
2.5
Vector string
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N
Attack Vector Network
Attack Complexity Low
Privileges Required Low
User Interaction Required
Scope Unchanged
Confidentiality Low
Integrity Low
Availability None

Threat Intelligence

EPSS Exploit Probability
16.9% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 1

CWE-93

Affected Products 2

VendorProductVersionRange
nodejsundici* <6.24.0
nodejsundici*≥7.0.0  –  <7.24.0

References 3

  • cna.openjsf.org https://cna.openjsf.org/security-advisories.html
    Vendor Advisory
  • github.com https://github.com/nodejs/undici/security/advisories/GHSA-4992-7rv2-5pvq
    MitigationPatchVendor Advisory
  • hackerone.com https://hackerone.com/reports/3487198
    Permissions Required

Remediation

  • github.com https://github.com/nodejs/undici/security/advisories/GHSA-4992-7rv2-5pvq
    MitigationPatchVendor Advisory