CVE-2026-93576 — Io.netty/netty-codec-smtp: netty netty-codec-smtp — smtp command-name field is not crlf-validated (incomplete fix of cve-2025-59419)
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 …
Published: 2026-09-18 · CVSS: 7.5 · CVSS 3.1
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.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7