GHSA-fv2f-rw9f-v9cm

Source

https://github.com/advisories/GHSA-fv2f-rw9f-v9cm

Import Source

https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/05/GHSA-fv2f-rw9f-v9cm/GHSA-fv2f-rw9f-v9cm.json

JSON Data

https://api.osv.dev/v1/vulns/GHSA-fv2f-rw9f-v9cm

Aliases

CVE-2026-38728

Published

2026-05-15T15:30:45Z

Modified

2026-06-29T23:26:32Z

Severity

8.7 (High) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N CVSS Calculator

Summary

smtp-server's command parser memory exhaustion denial-of-service

Details

smtp-server prior to v3.18.3 are vulnerable to unauthenticated memory exhaustion denial-of-service. smtp-server's command parser allows any remote client to consume server memory by sending data without newline characters. The server's _remainder buffer in SMTPStream._write grows without limit, leading to heap exhaustion, prolonged GC pauses that freeze the event loop, and in some cases, process crash.

The _write method in lib/smtp-stream.js appends incoming TCP chunks to this._remainder in command mode. The buffer is only emptied when a newline is found. If a client never sends a newline, the _remainder value will grow indefinitely, causing excess memory consumption.

Database specific

{
    "cwe_ids":  [
        "CWE-400"
    ],
    "github_reviewed":  true,
    "github_reviewed_at":  "2026-06-29T22:57:15Z",
    "nvd_published_at":  "2026-05-15T15:16:51Z",
    "severity":  "HIGH"
}

References

Affected packages

npm / smtp-server

Package

Name: smtp-server; View open source insights on deps.dev
Purl: pkg:npm/smtp-server

Affected ranges

Type: SEMVER
Events: Introduced

0 Unknown introduced version / All previous versions are affected

Fixed

3.18.3

Database specific

source

"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/05/GHSA-fv2f-rw9f-v9cm/GHSA-fv2f-rw9f-v9cm.json"