All vulnerabilities
CVE-2026-111943

Distrust compromised intermediate certificates in crypto/x509

Go standard library crypto/x509
CVSS
NoneNot scored
ExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.14%Chance of exploitation activity in the next 30 days, higher than 3% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed in1.26.10Also 1.27.3CVE List
Published21 Oct 2026Updated 21 Oct 2026CVE List

What fixes it

A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.

Description

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.

Text from CVE List

Affected versions 2

  • crypto/x509affected: all versions before 1.26.10CVE List
  • crypto/x509affected: 1.27.0-0 before 1.27.3CVE List

References 4