CVE-2026-42504 - Vulnerability Details - OpenCVE

Decoding a maliciously-crafted MIME header containing many invalid encoded-words can consume excessive CPU.

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
Golang	Mime

No data.

No data.

References

Link	Providers
https://go.dev/cl/774481
https://go.dev/issue/79217
https://groups.google.com/g/golang-announce/c/tKs3rmcBcKw
https://pkg.go.dev/vuln/GO-2026-5038

History

Wed, 03 Jun 2026 14:30:00 +0000

Type	Values Removed	Values Added
Weaknesses		CWE-407
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'}`

Wed, 03 Jun 2026 12:45:00 +0000

Type	Values Removed	Values Added
First Time appeared		Golang Golang mime
Vendors & Products		Golang Golang mime

Wed, 03 Jun 2026 04:30:00 +0000

Type	Values Removed	Values Added
Weaknesses		CWE-442

Wed, 03 Jun 2026 02:30:00 +0000

Type	Values Removed	Values Added
Description		Decoding a maliciously-crafted MIME header containing many invalid encoded-words can consume excessive CPU.
Title		Quadratic complexity in WordDecoder.DecodeHeader in mime
References		https://go.dev/cl/774481 https://go.dev/issue/79217 https://groups.google.com/g/golang-announce/c/tKs3rmcBcKw https://pkg.go.dev/vuln/GO-2026-5038

MITRE

Status: PUBLISHED

Assigner: Go

Published: 2026-06-02T22:01:37.219Z

Updated: 2026-06-03T14:06:13.623Z

Reserved: 2026-04-28T00:21:12.792Z

Link: CVE-2026-42504

Vulnrichment

Updated: 2026-06-03T14:05:35.965Z

NVD

Status : Received

Published: 2026-06-02T23:16:37.927

Modified: 2026-06-03T16:16:30.157

Link: CVE-2026-42504

Redhat

No data.

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