Improper input validation in Golang Go

CVE-2018-16873

In 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 the import path of a malicious Go package, or a package that imports it directly or indirectly. Specifically, it is only vulnerable in GOPATH mode, but not in module mode (the distinction is documented at https://golang.org/cmd/go/#hdr-Module_aware_go_get). Using custom domains, it's possible to arrange things so that a Git repository is cloned to a folder named ".git" by using a vanity import path that ends with "/.git". If the Git repository root contains a "HEAD" file, a "config" file, an "objects" directory, a "refs" directory, with some work to ensure the proper ordering of operations, "go get -u" can be tricked into considering the parent directory as a repository root, and running Git commands on it. That will use the "config" file in the original Git repository root for its configuration, and if that config file contains malicious commands, they will execute on the system running "go get -u".

Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)

EPSS: 0.663 (99.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2018-16873?
CVE-2018-16873 is a high-severity vulnerability in Golang Go, classified under Improper Input Validation. CVSS score: 8.1/10. Published 2018-12-14.
How severe is CVE-2018-16873?
High severity. CVSS v3 base score is 8.1 out of 10.
Is CVE-2018-16873 known to be exploited?
4 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.