CVE-2026-42499 - Vulnerability Details - OpenCVE

Pathological inputs could cause DoS through consumePhrase when parsing an email address according to RFC 5322.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploitation none

Automatable yes

Technical Impact partial

Vendors	Products
Go Standard Library	Net\/mail

No data.

No data.

References

Link	Providers
https://go.dev/cl/771520
https://go.dev/issue/78987
https://groups.google.com/g/golang-announce/c/qcCIEXso47M
https://pkg.go.dev/vuln/GO-2026-4977

History

Fri, 08 May 2026 22:15:00 +0000

Type	Values Removed	Values Added
Metrics		cvssV3_1 `{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}` ssvc `{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Thu, 07 May 2026 22:45:00 +0000

Type	Values Removed	Values Added
Weaknesses		CWE-674 CWE-729

Thu, 07 May 2026 22:15:00 +0000

Type	Values Removed	Values Added
First Time appeared		Go Standard Library Go Standard Library net\/mail
Vendors & Products		Go Standard Library Go Standard Library net\/mail

Thu, 07 May 2026 20:00:00 +0000

Type	Values Removed	Values Added
Description		Pathological inputs could cause DoS through consumePhrase when parsing an email address according to RFC 5322.
Title		Quadratic string concatenation in consumePhrase in net/mail
References		https://go.dev/cl/771520 https://go.dev/issue/78987 https://groups.google.com/g/golang-announce/c/qcCIEXso47M https://pkg.go.dev/vuln/GO-2026-4977

MITRE

Status: PUBLISHED

Assigner: Go

Published: 2026-05-07T19:41:18.615Z

Updated: 2026-05-08T21:29:59.662Z

Reserved: 2026-04-28T00:21:12.791Z

Link: CVE-2026-42499

Vulnrichment

Updated: 2026-05-08T16:55:43.428Z

NVD

Status : Undergoing Analysis

Published: 2026-05-07T20:16:44.540

Modified: 2026-05-08T22:16:33.183

Link: CVE-2026-42499

Redhat

No data.

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