Node nodemailer: Nodemailer 3.0.0 before 10.0.13 has a regular expression denial of service in
Affects node-nodemailerSource GCVE Database
Not known to be exploited · CVSS 7.5 High · fixed in 10.0.13 : patch node-nodemailer soon.
Data as of 28 Oct 2026, 23:29 UTC
- Patch
- Available – fixed in 10.0.13
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 14 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: 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 26 Oct 2026.
What to do
Affected software
| Product | 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– |
Ubuntu 24.04 LTSnode-nodemailerpkg:deb/ubuntu/node-nodemailer?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 22.04 LTSnode-nodemailerpkg:deb/ubuntu/node-nodemailer?arch=source&distro=jammyOther threats | Affected
| Fixed in– |
Ubuntu 20.04 LTSnode-nodemailerpkg:deb/ubuntu/node-nodemailer?arch=source&distro=focalOther 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
A fix is available in Nodemailer version 10.0.13 and later. Users should upgrade to version 10.0.13 or newer to remediate this vulnerability. No other mitigation steps are indicated.
Description
Nodemailer versions 3.0.0 before 10.0.13 contain a regular expression denial of service (ReDoS) vulnerability in the SMTPConnection._actionEHLO function. This vulnerability arises from overlapping whitespace sub-patterns in four AUTH mechanism detection regexes, causing quadratic backtracking. A malicious or man-in-the-middle SMTP server can exploit this by sending a crafted EHLO response with a long whitespace run and a non-matching token, which blocks the Node.js event loop for an extended period, potentially from tens of seconds to hours.
References
- ubuntu.com/security/CVE-2026-110869 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-110869 (opens in a new tab)
- github.com/nodemailer/nodemailer/security/advisories/GHSA-4ffr-jq9g-5ffx (opens in a new tab)
- vulncheck.com/advisories/nodemailer-3.0.0-before-10.0.13-redos-via-smtp-auth-mechanism-detection-regexes (opens in a new tab)