morgan is an HTTP request logger middleware for Node.js. In versions prior to 1.12.0, the internal helper that escapes log token values did not neutralize the Unicode line separator characters U+0085 (Next Line), U+2028 (Line Separator), and U+2029 (Paragraph Separator). An unauthenticated remote client can place these characters in an attacker-controlled log token, for example a Basic auth username surfaced through the remote-user token, so that Unicode-aware downstream log processing splits a single request log into multiple logical records. This is a log forging issue (CWE-117) and an incomplete-fix follow-up to CVE-2026-5078, which only addressed ASCII control characters. The issue is fixed in morgan 1.12.0, which extends the escaping set to cover these Unicode line separators. Upgrade to morgan 1.12.0 to remediate.

Project Subscriptions

Vendors Products
Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Fri, 28 Aug 2026 16:45:00 +0000

Type Values Removed Values Added
First Time appeared Morgan
Morgan morgan
Vendors & Products Morgan
Morgan morgan

Fri, 28 Aug 2026 15:30:00 +0000

Type Values Removed Values Added
Description morgan is an HTTP request logger middleware for Node.js. In versions prior to 1.12.0, the internal helper that escapes log token values did not neutralize the Unicode line separator characters U+0085 (Next Line), U+2028 (Line Separator), and U+2029 (Paragraph Separator). An unauthenticated remote client can place these characters in an attacker-controlled log token, for example a Basic auth username surfaced through the remote-user token, so that Unicode-aware downstream log processing splits a single request log into multiple logical records. This is a log forging issue (CWE-117) and an incomplete-fix follow-up to CVE-2026-5078, which only addressed ASCII control characters. The issue is fixed in morgan 1.12.0, which extends the escaping set to cover these Unicode line separators. Upgrade to morgan 1.12.0 to remediate.
Title morgan vulnerable to Log Forging via unescaped Unicode line separators
Weaknesses CWE-117
References
Metrics cvssV3_1

{'score': 5.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N'}


Projects

Sign in to view the affected projects.

cve-icon MITRE

Status: PUBLISHED

Assigner: openjs

Published:

Updated: 2026-08-28T13:41:49.521Z

Reserved: 2026-07-13T15:00:54.278Z

Link: CVE-2026-15603

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-08-28T16:17:07.417

Modified: 2026-08-28T16:17:07.417

Link: CVE-2026-15603

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-08-28T17:00:13Z

Weaknesses