All vulnerabilities
CVE-2026-94447

Checksum database bypass for golang.org/toolchain in cmd/go

Go toolchain cmd/go
Open in ThreatlineRecord JSON
CVSS
7.8High
ExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.10%Chance of exploitation activity in the next 30 days, higher than 0% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed in1.26.9Also 1.27.2CVE List
Published8 Oct 2026Updated 15 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

Previously, a user operating inside of a malicious Go project that defines a bogus golang.org/toolchain go.sum entry and operates a malicious GOMODPROXY the user chooses to use can bypass the intended checksum. We now ensure that golang.org/toolchain always goes to the network for the canonical checksum.

Text from CVE List

Affected versions 2

  • cmd/goaffected: all versions before 1.26.9CVE List
  • cmd/goaffected: 1.27.0-0 before 1.27.2CVE List

References 4