CVE-2021-23400

mediumpriority · track · 35EPSS 0.014 · 72 %ileEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

1.39% (72nd) EPSS

CVSS 6.8 · medium

Is it mine?

7 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · fstec_bdu · nvd

EPSS · scored 2026-10-27

The package nodemailer before 6.6.1 are vulnerable to HTTP Header Injection if unsanitized user input that may contain newlines and carriage returns is passed into an address object.

cvss

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

8.8

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.3–8.8

v2.06.8mediumAV:N/AC:M/Au:N/C:P/I:P/A:Pprimary · NVD / NIST USexploitability 8.6 · impact 6.4

v3.18.8highCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 2.8 · impact 5.9

v3.18.8highAV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU

v3.16.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L/E:Psecondary · ENISA EU

v3.16.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:Lsecondary · report@snyk.ioexploitability 2.8 · impact 3.4

v3.16.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:Lsecondary · OSV

v3.18.1highCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-74USprimaryCWE-74USCWE-74US

affected products (7)

Products and version ranges known to be affected.

n/a nodemailerunspecified → 6.6.1enisa_euvdEU
Andris Reinman Nodemailer≤ 6.6.1fstec_bduRU
Сообщество свободного программного обеспечения Debian GNU/Linux≤ 8fstec_bduRU
Сообщество свободного программного обеспечения Debian GNU/Linux≤ 9fstec_bduRU
Сообщество свободного программного обеспечения Debian GNU/Linux≤ 10fstec_bduRU
nodemailer nodemailer< 6.6.1nvdUScpe:2.3:a:nodemailer:nodemailer:*:*:*:*:*:*:*:*
npm nodemailer< 6.6.1osvUSpkg:npm/nodemailer

advisories (1)

Vendor and ecosystem advisories describing this.

GHSA-hwqf-gcqm-7353Header injection in nodemailer2021-12-10ghsa · osvUS
The package nodemailer before 6.6.1 are vulnerable to HTTP Header Injection if unsanitized user input that may contain newlines and carriage returns is passed into an address object.

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu nvd osv NVD CVE.org MITRE

published 2021-06-29modified 2026-06-17

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+5979 more

references (13)

External citations — patches, advisories, analysis.

scry

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