CVE-2021-23400
CVSS v3
8.8
HIGH
EPSS Score
1.4 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
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.
Technical details
- Published
- 2021-06-29
Frequently asked questions
What is 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.
Is CVE-2021-23400 actively exploited?
Active exploitation of CVE-2021-23400 has not been confirmed. Its EPSS score was 1.4% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2021-23400?
CVE-2021-23400 has a CVSS v3 base score of 8.8 (HIGH severity).
Is CVE-2021-23400 affecting your environment?
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