Nodemailer 5.0.0 through 10.0.1 TLS servername Cache Confusion
Nodemailer versions 5.0.0 through 10.0.1 use a process-global DNS cache that is keyed only by the DNS host, while each cache entry also stores the caller-specific TLS servername. When two direct TLS/SMTPS transports (secure: true) resolve the same non-IP host with different tls.servername values, the first transport's servername is returned on the cache hit and overwrites the second transport's explicitly configured value, so Nodemailer sends the wrong SNI value and validates the peer certificate against the wrong identity. In multi-tenant services or SNI-routed SMTP gateways, an attacker who can prime the cache can cause a victim transport to connect to the attacker's TLS virtual host and accept the attacker's certificate even with rejectUnauthorized: true, disclosing the victim's SMTP credentials. Fixed in 10.0.2.
CVE-2026-100701
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-100701
nodemailer
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"vendor": "nodemailer",
"product": "nodemailer",
"versions": [
{
"status": "affected",
"version": "5.0.0",
"lessThan": "10.0.2",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "10.0.2",
"versionType": "semver"
}
],
"packageURL": "pkg:npm/nodemailer",
"defaultStatus": "unaffected"
}
]- Related CVEs
- CVE-2026-100701
Source reference:
/cveMetadata/cveId
Publisher severity
medium
Source reference: /containers/cna/metrics
- Event
- #2446 · Revision 1
- Added to Heist Feed
- Publisher date