CVE-2026-39820 - Vulnerability Details - OpenCVE

Well-crafted inputs reaching ParseAddress, ParseAddressList, and ParseDate were able to trigger excessive CPU exhaustion and memory allocations.

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/759940
https://go.dev/issue/78566
https://groups.google.com/g/golang-announce/c/qcCIEXso47M
https://pkg.go.dev/vuln/GO-2026-4986

History

Fri, 08 May 2026 15:15:00 +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 21:45:00 +0000

Type	Values Removed	Values Added
First Time appeared		Go Standard Library Go Standard Library net/mail
Weaknesses		CWE-739
Vendors & Products		Go Standard Library Go Standard Library net/mail

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

Type	Values Removed	Values Added
Description		Well-crafted inputs reaching ParseAddress, ParseAddressList, and ParseDate were able to trigger excessive CPU exhaustion and memory allocations.
Title		Quadratic string concatentation in consumeComment in net/mail
References		https://go.dev/cl/759940 https://go.dev/issue/78566 https://groups.google.com/g/golang-announce/c/qcCIEXso47M https://pkg.go.dev/vuln/GO-2026-4986

MITRE

Status: PUBLISHED

Assigner: Go

Published: 2026-05-07T19:41:19.854Z

Updated: 2026-05-08T14:27:54.923Z

Reserved: 2026-04-07T18:13:03.526Z

Link: CVE-2026-39820

Vulnrichment

Updated: 2026-05-08T14:27:47.966Z

NVD

Status : Undergoing Analysis

Published: 2026-05-07T20:16:43.187

Modified: 2026-05-08T15:16:37.323

Link: CVE-2026-39820

Redhat

No data.

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