CVE-2021-38189
CVSS v3
9.8
CRITICAL
EPSS Score
1.5 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
An issue was discovered in the lettre crate before 0.9.6 for Rust. In an e-mail message body, an attacker can place a . character after two <CR><LF> sequences and then inject arbitrary SMTP commands.
Technical details
- Published
- 2021-08-08
Frequently asked questions
What is CVE-2021-38189?
An issue was discovered in the lettre crate before 0.9.6 for Rust. In an e-mail message body, an attacker can place a . character after two <CR><LF> sequences and then inject arbitrary SMTP commands.
Is CVE-2021-38189 actively exploited?
Active exploitation of CVE-2021-38189 has not been confirmed. Its EPSS score was 1.5% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2021-38189?
CVE-2021-38189 has a CVSS v3 base score of 9.8 (CRITICAL severity).
Is CVE-2021-38189 affecting your environment?
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