morgan vulnerable to Log Forging via unescaped Unicode line separators (morgan morgan)

CVE-2026-15603
MEDIUM 5.3

At a glance

Source
NVD
EPSS
EPSS 0.40 % · percentile 34 ()
State
PUBLISHED
Published
Updated
Assigner
openjs
NVD status
Analyzed

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.

Weaknesses (CWE)

  • CWE-117 — Improper Output Neutralization for Logs

References

Scores

VersionScoreVectorScored by
CVSS 3.1MEDIUM 5.3CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:Nopenjs
CVSS 3.1MEDIUM 5.3CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:NNVD · ce714d77-add3-4f53-aff5-83d477b104bb (Secondary)

Advisories

European references

CERT-FR advisories

Affected configurations (NVD CPE)

Affected products

ProductVersions
morgan · morganaffected 0 < 1.12.0

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD