CVE-2026-100699Medium· 5.3▾ TwilightPoC availableNodemailer is a Node.js email-sending library. In versions >= 9.1.0 and < 10.0.9, the address parser (src/addressparser) mishandles addresses whose local-part is a quoted string and that are followed by RFC 5322 comments, allowing traili…
▾ Twilight zone — High severity, or a signal on a lesser flaw
impact 29.2 · likelihood 0 · exploitation 12
A public proof-of-concept already exists for this vulnerability — see Exploit availability below.
Stakeholder-Specific Vulnerability Categorization from CISA's ADP record at CVE.org: whether exploitation is observed, whether an attack can be automated, and how much of the system is at stake.
Exploit-prediction probability, daily snapshots since Sep 28.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via NVD
0.2%
Exploit / PoC code exists
Last analysed / modified upstream
0.2% → 0.2%
Nodemailer is a Node.js email-sending library. In versions >= 9.1.0 and < 10.0.9, the address parser (src/addressparser) mishandles addresses whose local-part is a quoted string and that are followed by RFC 5322 comments, allowing trailing comment-separated domain atoms to be retained in the normalized address. For example, the input "user"@example.com(x)evil.com is parsed to the address value '[email protected] evil.com', which contains additional attacker-controlled domain text separated by a literal space. This parsed value is used without further strict recipient validation when the message envelope is built (envelope.to in src/mime-node), so a malformed/ambiguous recipient address can be accepted and placed in the SMTP envelope. Whether this results in delivery to an unintended recipient on real SMTP servers has not been confirmed. The issue is a variant of the RFC 5322 comment parsing problem addressed in GHSA-cc9r-2j5m-2m83, affecting the separate quoted-local-part code path. Version 10.0.9 contains a fix.
Refer to the linked advisories for vendor-supplied fixes and affected version ranges.
Field changes observed since this record was first indexed.
Connected by shared product, vendor, weakness, or advisory.
CVE-2026-110870Medium· 5.3Nodemailer from 3.0.0 before 10.0.13 contains an improper input validation vulnerability in its address parser that fails to strip RFC 5322 comments inside angle-bracket addresses
CVE-2026-92597Medium· 6.5Nodemailer versions >= 6.9.16 and < 9.1.0 mis-parse RFC 5322 comments in email addresses: in lib/addressparser, a comment closed immediately before a non-break character causes the tokenizer to concatenate the atoms surrounding the comme…
CVE-2026-110872Medium· 5.9Nodemailer from 3.0.0 before 10.0.10 contains a quadratic complexity denial of service vulnerability in the SMTP client reply parser in SMTPConnection._onData and isPartialResponse
CVE-2026-110871Medium· 6.5Nodemailer from 3.0.0 before 10.0.10 contains a denial of service vulnerability in MessageParser.parseHeaders that allows users to exhaust CPU through quadratic header unfolding
CVE-2026-110869High· 7.5Nodemailer 3.0.0 before 10.0.13 has a regular expression denial of service in SMTPConnection._actionEHLO, whose four AUTH mechanism detection regexes contain overlapping whitespace sub-patterns that backtrack quadratically
CVE-2026-100700High· 7.5nodemailer before 10.0.6 contains a denial of service vulnerability in the addressparser free-text fallback regex pattern that exhibits quadratic backtracking behavior