CVE-2026-33811highCWE-1341

CVE-2026-33811: high-severity vulnerability in Go standard library net

Crash when handling long CNAME response in net

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21Vexday Risk Score

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

ssvc Trackcvss 7.5epss 0.9%
When using LookupCNAME with the cgo DNS resolver, a very long CNAME response can trigger a double-free of C memory and a crash.
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
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