CVE-2026-27140

SWIG file names containing 'cgo' and well-crafted payloads could lead to code smuggling and arbitrary code execution at build time due to trust layer bypass.

What this means for your business

It affects Golang Go. It matters if your company, or a supplier that handles your data, runs it.
An attacker can use it remotely, over a network, without a login, but only after tricking someone into an action such as opening a file or a link.
FIRST's prediction model gives it a 0.7% chance of attack attempts being seen in the next 30 days, ranking above 49% of all known flaws.

What to do

1Check whether your company or your suppliers run Golang Go, and which version. The affected versions are listed further down this page.
2If you do, apply the vendor's fix. A patch or vendor advisory has been published.

Not sure if your company is exposed?

Fastnexa’s certified penetration testers can check whether attackers could use this flaw, or others like it, against your websites, apps and network. The full test is free for our first 10 founding clients until 31 December 2026.

Check if you’re exposed Book a call

Scoring

CVSS: 8.8 (v3.1)
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Weakness: CWE-863
Assigned by: security@golang.org

Dates

Published: 2026-04-08
Last modified: 2026-09-10
Sources: NVD

Affected products

Golang Go- 1.25.9, 1.26.0 - 1.26.2

As listed in the NVD configuration data. Not a statement about your estate.