Arbitrary code execution via go.mod toolchain directive in cmd/go
Priority MEDIUM 52CWE-94Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Code execution
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-94.
Summary
The go.mod toolchain directive, introduced in Go 1.21, can be leveraged to execute scripts and binaries relative to the root of the module when the "go" command was executed within the module. This applies to modules downloaded using the "go" command from the module proxy, as well as modules downloaded directly using VCS software.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.01757 78th percentileScored 2026-11-07
Fix Fixed cmd/go (Go toolchain): 1.21.1
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Go standard library | cmd/go | 1.21.0-0 to before 1.21.1 | 1.21.1 | Patch available | CNA |
- cmd/go VendorGo standard library Affected 1.21.0-0 to before 1.21.1 Fixed in 1.21.1 Patch available CNA
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:golang:go:*:*:*:*:*:*:*:* | 1.21.0 to before 1.21.1 | Vulnerable | Go standard library |
- cpe:2.3:a:golang:go:*:*:*:*:*:*:*:* Versions 1.21.0 to before 1.21.1 Vulnerable ·Go standard library
Remediation
- Fix · CNA cmd/go (Go toolchain) Fixed in 1.21.1
Vendor assessments
Red Hat
Red Hat rating: Important. Red Hat's page for this CVE →
Not affected: 6 products
- OpenShift Service Mesh 2
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
- Red Hat OpenShift Container Platform 4
- Red Hat OpenShift Virtualization 4
- Red Hat Storage 3
Timeline
- 2026-10-02 Threatist record created from CVE-2023-39320
- 2026-10-03 Alias added: GHSA-rxv8-v965-v333
References
More Go standard library Go vulnerabilities
- TI-2020-00578 Improper certificate validation in Microsoft Windows KEVCVSS 3.1HIGH 8.1
- TI-2023-23979 The HTTP/2 protocol allows a denial of service (server resource consumption) because… KEVCVSS 3.1HIGH 7.5
- TI-2018-05208 The "go get" implementation in Go 1.9.4, when the -insecure command-line option is used… CVSS 3.1HIGH 8.8
- TI-2018-12083 Improper input validation in [UNKNOWN] golang CVSS 3.1HIGH 8.1
- TI-2024-16306 Mishandling of corrupt central directory record in archive/zip CVSS 3.1MEDIUM 5.5
- TI-2021-15910 Go before 1.16.9 and 1.17.x before 1.17.2 has a Buffer Overflow via large arguments in a… CVSS 3.1CRITICAL 9.8
Sources
- CVE-2023-39320 · CVE Program
- CVE-2023-39320 · NVD
- FIRST EPSS
- GHSA-rxv8-v965-v333 · GitHub Advisory Database · CC BY 4.0
- CVE-2023-39320 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences