CVE-2026-39820

HIGH

Quadratic string concatentation in consumeComment in net/mail

Title source: cna
STIX 2.1

Description

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

References (4)

Core 4

Scores

CVSS v3 7.5
EPSS 0.0005
EPSS Percentile 16.8%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact partial

Details

CWE
CWE-770
Status published
Products (3)
Go standard library/net/mail < 1.25.10
Go standard library/net/mail 1.26.0-0 - 1.26.3
golang/go < 1.25.10
Published May 07, 2026
Tracked Since May 08, 2026