CVE-2026-39820highCWE-606

CVE-2026-39820: high-severity vulnerability in Go standard library net/mail

Quadratic string concatentation in consumeComment in net/mail

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21Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 7.5epss 0.8%
Well-crafted inputs reaching ParseAddress, ParseAddressList, and ParseDate were able to trigger excessive CPU exhaustion and memory allocations.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected products
Go standard library · net/mail
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