CVE-2026-93576

A flaw was found in Netty netty-codec-smtp. The component does not properly validate Carriage Return (CR) and Line Feed (LF) characters in the SMTP command-name field. A remote attacker, if an application routes untrusted input into this field, can embed CR/LF characters to inject arbitrary SMTP commands. This can lead to SMTP command smuggling, allowing for unauthorized email relay or spoofing of sender/recipient addresses. While the impact is significant, the real-world exploitability is considered lower as applications typically do not place user-controlled data in the command-name field.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/security/cve/CVE-2026-93576
https://bugzilla.redhat.com/show_bug.cgi?id=2536968

Configurations

No configuration.

History

18 Sep 2026, 21:18

Type	Values Removed	Values Added
Summary	~~(en) Netty netty-codec-smtp — SMTP command-name field is not CRLF-validated (incomplete fix of CVE-2025-59419)~~	(en) A flaw was found in Netty netty-codec-smtp. The component does not properly validate Carriage Return (CR) and Line Feed (LF) characters in the SMTP command-name field. A remote attacker, if an application routes untrusted input into this field, can embed CR/LF characters to inject arbitrary SMTP commands. This can lead to SMTP command smuggling, allowing for unauthorized email relay or spoofing of sender/recipient addresses. While the impact is significant, the real-world exploitability is considered lower as applications typically do not place user-controlled data in the command-name field.

18 Sep 2026, 15:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-18 15:17

Updated : 2026-09-25 09:17

NVD link : CVE-2026-93576

Mitre link : CVE-2026-93576

CVE.ORG link : CVE-2026-93576

JSON object : View

Products Affected

No product.

CWE

CWE-93

Improper Neutralization of CRLF Sequences ('CRLF Injection')

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