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CVE-2026-93576 (GCVE-0-2026-93576)

Vulnerability from cvelistv5 – Published: 2026-09-18 14:33 – Updated: 2026-09-18 20:10
VLAI
Title
Io.netty/netty-codec-smtp: netty netty-codec-smtp — smtp command-name field is not crlf-validated (incomplete fix of cve-2025-59419)
Summary
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.
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-18 14:58 UTC
CWE
  • CWE-93 - Improper Neutralization of CRLF Sequences ('CRLF Injection')
References
URL Tags
https://access.redhat.com/security/cve/CVE-2026-93576 vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2536968 issue-trackingx_refsource_REDHAT
Impacted products
Vendor Product Version CPE status
Red Hat Red Hat build of Apache Camel for Spring Boot 4     cpe:/a:redhat:camel_spring_boot:4
Create a notification for this product.
Red Hat Red Hat Fuse 7     cpe:/a:redhat:jboss_fuse:7
Create a notification for this product.
Red Hat Red Hat JBoss Enterprise Application Platform 7     cpe:/a:redhat:jboss_enterprise_application_platform:7
Create a notification for this product.
Red Hat Red Hat Single Sign-On 7     cpe:/a:redhat:red_hat_single_sign_on:7
Create a notification for this product.
Date Public
2026-09-10 00:53
Show details on NVD website

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Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

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Detection rules are retrieved from Rulezet.

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Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.


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