CVE-2026-100701: Node nodemailer · 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
Affects node-nodemailerSource GCVE Database
Not known to be exploited · CVSS 5.9 Medium · fixed in 10.0.2 : update node-nodemailer when convenient.
Data as of 11 Nov 2026, 23:24 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 1% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 10.0.2
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:L/A:NExploitation evidence
Disclosed: evidence found.
CVE published 26 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 11 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
npmnodemailerpkg:npm/nodemailerOther threats | Affected
| Fixed in– |
Ubuntu 20.04 LTSnode-nodemailerpkg:deb/ubuntu/node-nodemailer?arch=source&distro=focalOther threats | Affected
| Fixed in– |
Ubuntu 22.04 LTSnode-nodemailerpkg:deb/ubuntu/node-nodemailer?arch=source&distro=jammyOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSnode-nodemailerpkg:deb/ubuntu/node-nodemailer?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 26.10node-nodemailerpkg:deb/ubuntu/node-nodemailer?arch=source&distro=stonkingOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSnode-nodemailerpkg:deb/ubuntu/node-nodemailer?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Upgrade Nodemailer to version 10.0.2 or later, where this DNS caching and SNI handling issue is fixed. No other mitigation is indicated by the vendor advisory. Users should ensure they are not using affected versions.
Description
Nodemailer versions 5.0.0 through 10.0.1 have a vulnerability in their DNS caching mechanism where the cache key is only the DNS host, but cache entries also store a caller-specific TLS servername. This causes the wrong SNI value to be sent when multiple TLS transports resolve the same host with different servernames, leading to incorrect certificate validation. An attacker able to prime the cache can cause a victim to connect to the attacker's TLS host and accept a malicious certificate, potentially exposing SMTP credentials. The issue is fixed in Nodemailer version 10.0.2.
References
- github.com/nodemailer/nodemailer/security/advisories/GHSA-6vj9-mwq6-2f5v (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-100701 (opens in a new tab)
- vulncheck.com/advisories/nodemailer-5.0.0-through-10.0.1-tls-servername-cache-confusion (opens in a new tab)
- ubuntu.com/security/CVE-2026-100701 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-100701 (opens in a new tab)