CVE-2026-111943mediumCWE-299

CVE-2026-111943: medium-severity vulnerability in Go standard library crypto/x509

Distrust compromised intermediate certificates in crypto/x509

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33Vexday Risk Score

No sign of exploitation. It has a public proof of concept.

ssvc Attendcvss 6.8epss 0.4%
from disclosure to weaponsame day
Published on NVDOct 21
1st PoCOct 21
On most platforms, Go uses the given system root certificates. However, in some narrower cases, the system trust stores may not be updated without further action. To defend against the narrower set of cases that may remain affected, a denylist was added in crypto/x509 to return an error when calling Verify with any of the known intermediate certificates that are no longer considered to be trustworthy.
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N
Affected products
Go standard library · crypto/x509
⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
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