Description
Downloading and building modules with malicious version strings can cause local code execution. On systems with Mercurial (hg) installed, downloading modules from non-standard sources (e.g., custom domains) can cause unexpected code execution due to how external VCS commands are constructed. This issue can also be triggered by providing a malicious version string to the toolchain. On systems with Git installed, downloading and building modules with malicious version strings can allow an attacker to write to arbitrary files on the filesystem. This can only be triggered by explicitly providing the malicious version strings to the toolchain and does not affect usage of @latest or bare module paths.
References (4)
Core 4
Core References
Patch
https://go.dev/cl/736710
Issue Tracking, Patch
https://go.dev/issue/77099
Release Notes, Mailing List
https://groups.google.com/g/golang-announce/c/Vd2tYVM8eUc
Vendor Advisory
https://pkg.go.dev/vuln/GO-2026-4338
Scores
CVSS v3
7.0
EPSS
0.0002
EPSS Percentile
4.5%
Attack Vector
LOCAL
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
total
Details
CWE
CWE-787
Status
published
Products (1)
golang/go
< 1.24.12
Published
Jan 28, 2026
Tracked Since
Feb 18, 2026