CVE-2026-42499

Description

A flaw was found in the net/mail package within the Go standard library. A remote attacker could provide specially crafted, pathological email addresses. When these malformed email addresses are parsed by the consumePhrase function, it can lead to excessive resource consumption due to quadratic string concatenation, resulting in a Denial of Service (DoS) condition.

Statement

This is an Important denial of service vulnerability in the net/mail package of the Go standard library. A remote attacker can exploit this flaw by sending specially crafted email addresses, leading to excessive resource consumption and a denial of service in Go applications that parse email addresses using the affected library.

Mitigation

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.

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
ConfidentialityNoneN/ANone
Integrity ImpactNoneN/ANone
Availability ImpactHighN/AHigh

Vector

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

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

Understanding the Weakness (CWE)

Other

Technical Impact: Reduce Performance

This issue can make the product perform more slowly. If the relevant code is reachable by an attacker, then this could be influenced to create performance problem.

Frequently Asked Questions

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