CVE-2021-23400
HTTP Header Injection
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- Low
Exploit likelihood
What each source reports
CVE List Score used
HTTP Header Injection
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.
- Record
CVE-2021-23400- CVSS 3.1
- 6.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L/E:P - Updated
- 2026-11-02
EUVDEUVD-2021-2533
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.
- Record
EUVD-2021-2533- CVSS 3.1
- 6.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L/E:P - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-hwqf-gcqm-7353
Header injection in nodemailer
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.
- Record
GHSA-hwqf-gcqm-7353- CVSS 3.1
- 6.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L - Weakness
- CWE-74
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2021-23400- CVSS 3.1
- 6.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L - CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - CVSS 2.0
- 6.8 Medium
AV:N/AC:M/Au:N/C:P/I:P/A:P - Weakness
- CWE-74
- Updated
- 2026-11-02
OSV
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.
- Record
CVE-2021-23400- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVDEBIAN-CVE-2021-23400
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.
- Record
DEBIAN-CVE-2021-23400- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVGHSA-hwqf-gcqm-7353
Header injection in nodemailer
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.
- Record
GHSA-hwqf-gcqm-7353- CVSS 3.1
- 6.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L - Weakness
- CWE-74
- Updated
- 2026-11-02
OSVUBUNTU-CVE-2021-23400
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.
- Record
UBUNTU-CVE-2021-23400- CVSS 3.1
- 6.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L - CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVCLSA-2026-1775003161 No score
TuxCare security update for nodemailer (6 CVEs)
TuxCare rebuilt nodemailer to address 6 CVEs. Fixed in 2.7.2-tuxcare.1.
- Record
CLSA-2026-1775003161- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
nodemailernpm |
before 6.6.1 | 6.6.1 |
nodemailerTuxCare:npm From an advisory covering 4 CVEs |
2.7.2-tuxcare.0 up to 2.7.2-tuxcare.1, plus listed versions 2.7.2 |
2.7.2-tuxcare.1 |
node-nodemailerDebian:12 |
before 6.4.17-3 | 6.4.17-3 |
node-nodemailerDebian:13 |
before 6.4.17-3 | 6.4.17-3 |
node-nodemailerDebian:14 |
before 6.4.17-3 | 6.4.17-3 |
node-nodemailerUbuntu:20.04:LTS |
All versions, plus listed versions 6.3.0-26.3.1-16.4.0-16.4.1-16.4.2-16.4.5-1 |
None known |
node-nodemailerUbuntu:22.04:LTS |
All versions, plus listed versions 6.4.17-36.7.0-16.7.0-26.7.1+~6.4.4-1 |
None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected | ||
| facts | ||
| aliases, published | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-23400 is a medium vulnerability (CVSS 6.3) in Nodemailer, published June 29, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.39%, the 72nd percentile. Fixed in nodemailer 6.6.1.
References
snyk.io/vuln/SNYK-JS-NODEMAILER-1296415
github.com/nodemailer/nodemailer/issues/1289
nvd.nist.gov/vuln/detail/CVE-2021-23400
security-tracker.debian.org/tracker/CVE-2021-23400
ubuntu.com/security/CVE-2021-23400
cve.org/CVERecord?id=CVE-2021-23400