CVE-2026-32178

Description

A flaw was found in the .NET runtime (System.Net.Mail) in how email address data is parsed. Improper neutralization of special characters, specifically carriage return and line feed (CR/LF) sequences, may allow specially crafted email address input to be interpreted incorrectly. An attacker could exploit this issue to perform email spoofing by injecting additional headers or altering how the email address is processed during SMTP operations

Statement

This Important flaw in the .NET runtime's System.Net.Mail component affects Red Hat Enterprise Linux and Red Hat Hardened Images. Improper neutralization of carriage return and line feed sequences during email address parsing can lead to SMTP command or header injection, enabling email spoofing in applications utilizing the affected .NET versions for SMTP operations.

The impact is primarily related to how email data is handled and interpreted. By injecting crafted header content, an attacker may influence the structure of email messages and potentially expose sensitive information included in those messages to unintended recipients.

Mitigation

Red Hat is not aware of a practical temporary workaround that fully mitigates this issue or meets Red Hat Product Security's standards for usability, deployment, applicability, or stability. Customers are advised to apply the relevant security updates when they become available.

Common Vulnerability Scoring System (CVSS) Score Details

Info alert:Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score7.5N/A7.5
Attack VectorNetworkN/ANetwork
Attack ComplexityLowN/ALow
Privileges RequiredNoneN/ANone
User InteractionNoneN/ANone
ScopeUnchangedN/AUnchanged
ConfidentialityHighN/AHigh
Integrity ImpactNoneN/ANone
Availability ImpactNoneN/ANone

Vector

Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Understanding the Weakness (CWE)

Confidentiality,Integrity,Availability,Other

Technical Impact: Execute Unauthorized Code or Commands; Alter Execution Logic; DoS: Crash, Exit, or Restart

Frequently Asked Questions

Want to get errata notifications? Sign up here.