GHSA-4vj7-5mj6-jm8m

Suggest an improvement
Source
https://github.com/advisories/GHSA-4vj7-5mj6-jm8m
Import Source
https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/07/GHSA-4vj7-5mj6-jm8m/GHSA-4vj7-5mj6-jm8m.json
JSON Data
https://api.osv.dev/v1/vulns/GHSA-4vj7-5mj6-jm8m
Aliases
Downstream
CGA (14)
MINI (2)
Published
2026-07-10T14:32:15Z
Modified
2026-09-10T03:51:10Z
Severity
  • 5.3 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N CVSS Calculator
Summary
morgan vulnerable to Log Forging via unneutralized control characters in :remote-user
Details

Impact

Morgan's :remote-user token extracts the Basic auth username from the Authorization header and writes it to the log stream without neutralizing control characters. An attacker can send a crafted Authorization: Basic header containing CR/LF characters to inject forged log lines, corrupting the one-request-per-line structure of access logs.

The built-in combined, common, default, and short formats are affected, as well as any custom format that includes :remote-user.

Patches

Users should upgrade to version 1.11.0.

Workarounds

Use a custom format string that does not include :remote-user.

Database specific 
{
    "cwe_ids":  [
        "CWE-117"
    ],
    "github_reviewed":  true,
    "github_reviewed_at":  "2026-07-10T14:32:15Z",
    "nvd_published_at":  "2026-06-03T08:16:19Z",
    "severity":  "MODERATE"
}
References

Affected packages

npm / morgan

Package

Name
morgan
View open source insights on deps.dev
Purl
pkg:npm/morgan

Affected ranges

Type
SEMVER
Events
Introduced
1.2.0
Fixed
1.11.0

Database specific

last_known_affected_version_range 
"<= 1.10.1"
source 
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/07/GHSA-4vj7-5mj6-jm8m/GHSA-4vj7-5mj6-jm8m.json"