# CVE-2021-38189: RUSTSEC-2021-0069 - SMTP command injection in body

Source: https://junglewise.ai/threats/cve-2021-38189-smtp-command-injection-in-lettre  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2021-05-22  
License: CC BY 4.0 with a link back

CVE-2021-38189 · Severity: low · CVSS 3.1 · Published 2021-05-22

SMTP command injection in body

Technologies: [lettre (crates.io)](https://junglewise.ai/threats/technologies/crates-io-lettre). Vendors: [crates.io](https://junglewise.ai/threats/vendors/crates-io).

## Quick answers

**Is CVE-2021-38189 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2021-38189 being exploited in the wild.

**How severe is CVE-2021-38189?** Low severity, with a CVSS score of 3.1, published 22 May 2021.

**Which products and versions are affected?** lettre (crates.io) SEMVER:introduced=0.7.0,fixed=0.9.6, SEMVER:introduced=0.7.0,fixed=0.9.6,introduced=0.10.0-alpha.1,fixed=0.10.0-rc.3.

**Is there a fix for CVE-2021-38189?** Yes. lettre (crates.io): upgrade to 0.10.0-rc.3, 0.9.6 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2021-38189?** Check whether you run lettre (crates.io) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- lettre (crates.io): upgrade to 0.10.0-rc.3, 0.9.6 or later

  ```sh
  cargo update -p lettre
  ```


## Affected products

- lettre (crates.io) SEMVER:introduced=0.7.0,fixed=0.9.6, SEMVER:introduced=0.7.0,fixed=0.9.6,introduced=0.10.0-alpha.1,fixed=0.10.0-rc.3

## Identifiers

- CVE-2021-38189
- GHSA-qc36-q22q-cjw3
- RUSTSEC-2021-0069

## Related threats

- [lettre TLS hostname verification bypass in boring-tls backend](https://junglewise.ai/threats/cve-2026-46428-lettre-tls-hostname-verification-bypass-in-boring-tls-backend)
- [RUSTSEC-2020-0069 - Argument injection in sendmail transport](https://junglewise.ai/threats/cve-2020-28247-argument-injection-in-lettre)