Skip to content
Noroxi
CVE-2023-39320· NVD / CVE Program· CNA Go

Arbitrary code execution via go.mod toolchain directive in cmd/go

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.

CriticalCVSS 9.8 · v3.1—Proof of concept Fix available
Published
Sep 8, 2023
Updated
Jun 17, 2026
EPSS
1.8% · 77th percentile
Follow this CVE

Sign in to follow · You’ll be notified if a followed record enters KEV, gets an exploit or is updated.

Report tools

JSON

Action score

40

Plan

Add it to your regular patch cycle.

CVSS
39 / 40 · 9.8 / 10
CISA KEV
0 / 30 · Not listed
EPSS
1 / 30 · 1.8%

CISA SSVC decision

Exploitation
none
Automatable
yes
Technical impact
total

Vulnrichment: CISA's decision-tree inputs.

Affected systems

VendorProduct
golanggo

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • golang go1.21.0 and later · before 1.21.1

Versions reported by the vendor

Affected version ranges reported by the assigning authority (Go). Independent of NVD's CPE analysis and usually ahead of it.

  • Go toolchain cmd/go

    • 1.21.0-0 and later · before 1.21.1affected · semver

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Gotoolchainfrom 1.21.0-0 · before 1.21.11.21.1
openSUSE:Tumbleweedgo1.21before 1.21.1-1.11.21.1-1.1
SUSE:Linux Enterprise Module for Development Tools 15 SP4go1.21before 1.21.1-150000.1.6.11.21.1-150000.1.6.1
SUSE:Linux Enterprise Module for Development Tools 15 SP4go1.21before 1.21.1-150000.1.6.11.21.1-150000.1.6.1
SUSE:Linux Enterprise Module for Development Tools 15 SP4go1.21-opensslbefore 1.21.4.1-150000.1.5.11.21.4.1-150000.1.5.1
SUSE:Linux Enterprise Module for Development Tools 15 SP4go1.21-opensslbefore 1.21.4.1-150000.1.5.11.21.4.1-150000.1.5.1
SUSE:Package Hub 12gobefore 1.21-41.11.21-41.1
SUSE:Package Hub 12go1.21before 1.21.3-2.11.21.3-2.1

Other highest-scoring records for the same primary product.

  • CVE-2018-7187The "go get" implementation in Go 1.9.4, when the -insecure command-line option is used, does not validate the import path (get/vcs.go only
    54Plan
  • CVE-2018-16873In Go before 1.10.6 and 1.11.x before 1.11.3, the "go get" command is vulnerable to remote code execution when executed with the -u flag and
    52Plan
  • CVE-2021-38297Go before 1.16.9 and 1.17.x before 1.17.2 has a Buffer Overflow via large arguments in a function invocation from a WASM module, when GOARCH
    42Plan
  • CVE-2019-14809net/url in Go before 1.11.13 and 1.12.x before 1.12.8 mishandles malformed hosts in URLs, leading to an authorization bypass in some applica
    42Plan
  • CVE-2015-5739The net/http library in net/textproto/reader.go in Go before 1.4.3 does not properly parse HTTP header keys, which allows remote attackers t
    42Plan
  • CVE-2017-15041Go before 1.8.4 and 1.9.x before 1.9.1 allows "go get" remote command execution.
    42Plan

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
Go toolchain cmd/go1.21.1Vendor (CNA)
Go:toolchain1.21.1Package registry (OSV)
opensuse:go1.211.21.1-150000.1.6.1 · openSUSE:Leap 15.4Package registry (OSV)
opensuse:go1.21-openssl1.21.4.1-150000.1.5.1 · openSUSE:Leap 15.4Package registry (OSV)
suse:go1.21-41.1 · SUSE:Package Hub 12Package registry (OSV)
suse:go1.211.21.1-150000.1.6.1 · SUSE:Linux Enterprise Module for Development Tools 15 SP4Package registry (OSV)
suse:go1.21-openssl1.21.4.1-150000.1.5.1 · SUSE:Linux Enterprise Module for Development Tools 15 SP4Package registry (OSV)

Exploit status

Proof of concept available

A public proof of concept or detection signature exists. Exploit knowledge is out there; don't delay patching.

Evidence

  • Proof-of-concept repository on GitHub ×1

Noroxi does not host or link to exploit code. Metasploit module names and Nuclei template ids are shown (names, not code); Exploit-DB entries and PoC repositories are given as counts only.

Public exploit evidence
SourceKindDate
Proof-of-concept repository on GitHubstars:12024-02-24

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

  1. Published
  2. First PoC+168 d
  3. TodaySep 30, 2026+1118 d
EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
high · data can be read
Integrity
high · data or configuration can be modified
Availability
high · the service can be disrupted
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
High
Integrity impact
High
Availability impact
High

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

nvd-primary

Noroxi analysis

No Noroxi analysis for this record yet

We don't hand-write analysis for all 385,000+ vulnerabilities; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.

We use this product, ask for help

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

All records