High severity · published Oct 8, 2026
CVE-2026-94447
Checksum database bypass for golang.org/toolchain in cmd/go
7.8
CVSS
0.1%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Attack vector
Local
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.1% · higher than 1% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CM
cmd/go · Go toolchain
before 1.26.9; 1.27.0-0 before 1.27.2 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-94447
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-94447
go.dev
https://go.dev/cl/840785
go.dev
https://go.dev/issue/81834
groups.google.com
https://groups.google.com/g/golang-announce/c/U2fTuyDJznI
pkg.go.dev
https://pkg.go.dev/vuln/GO-2026-6602
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