CVE-2026-94447: Checksum database bypass for golang.org/toolchain in cmd/go
Advisory generated from the CVE record, CISA, Exploit Observer and VEDAS: what it is, whether it is exploited, who is affected, and how to fix and detect it.
Generated by VEDAS. Scores as of 2026-11-01 19:19 UTC. Rebuilt every few hours from cve-scores, CISA KEV and vedas-signatures. How this works and its limits.
What it is
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.
Description quoted from the CVE record (assigned by Go, published 2026-10-08).
Weakness: CWE-354 Improper Validation of Integrity Check Value
How it can be exploited
Exploitable with local access with low attack complexity needing no privileges and a user must take an action. Impact: confidentiality high, integrity high, availability high. CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CISA assessment (SSVC): CISA has no evidence of exploitation. Automatable: no. Technical impact: total.
Public exploit evidence (Exploit Observer)
Exploit Observer evidence for this CVE has not been fetched yet.
Live scores
- EPSS
- 0.001
low predicted chance of attack - VEDAS
- 0.055
little exploit evidence - On CISA KEV
- Not listed
- Detection rule
- None yet
Who is affected
| Product | Affected | Not affected |
|---|---|---|
| Go toolchain cmd/go | before 1.26.9 from 1.27.0-0 before 1.27.2 | Not stated |
Version ranges exactly as the CVE record states them. “Before X” means X is the first fixed version.
How to fix it
Fixed versions stated in the CVE record: 1.26.9, 1.27.2.
How to detect it
There is no open VEDAS detection rule for this bug yet. It is listed on the detection gaps page if CISA has confirmed attacks.
Advisories on this CVE
- Go 1.27.2 and 1.27.3: 15 security fixes including HTTP/2 server crashes, then a crypto/x509 distrust of the eMudhra intermediates (full advisory)
- Go: two security releases, HTTP/2 and toolchain fixes then eMudhra distrust (CVE-2026-78659, CVE-2026-78667, CVE-2026-78669, CVE-2026-97032, CVE-2026-97031, CVE-2026-94447, CVE-2026-97030) (19 Oct 2026)
References
Other references
- https://go.dev/cl/840785
- https://go.dev/issue/81834
- https://groups.google.com/g/golang-announce/c/U2fTuyDJznI
- https://pkg.go.dev/vuln/GO-2026-6602
Other databases
Where this comes from
This advisory is generated automatically by VEDAS from: CVE.org record, cve-scores (EPSS and VEDAS). Text in quotes is reproduced from the source; everything else is a fixed template filled with source fields. Nothing here is written by a language model. Check the vendor advisory before acting, and read how VEDAS and Exploit Observer work, and their limits.