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Vulnerability DatabaseRUSTSEC-2021-0069

RUSTSEC-2021-0069: 
Rust vulnerability analysis and mitigation

Overview

The vulnerability (RUSTSEC-2021-0069/CVE-2021-38189) was discovered in the lettre crate, a Rust email library, affecting versions before 0.9.6. The issue was publicly disclosed on August 8, 2021. The vulnerability allows attackers to inject arbitrary SMTP commands through email message bodies by manipulating dot character sequences (NVD CVE).

Technical details

The vulnerability is classified as a Command Injection vulnerability (CWE-77) with a CVSS v3.1 Base Score of 9.8 (CRITICAL) and vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. The issue occurs when an attacker can place a dot character after two specific sequences in an email message body, enabling the injection of arbitrary SMTP commands (NVD CVE).

Impact

The vulnerability allows attackers to execute arbitrary SMTP commands through email message manipulation, potentially leading to high impacts on confidentiality, integrity, and availability of the affected systems (NVD CVE).

Mitigation and workarounds

Users should upgrade to lettre crate version 0.9.6 or later to address this vulnerability. The fix involves proper handling of transparency codec in the SMTP transport implementation (Github PR).

Additional resources

Source: This report was generated using AI

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