8.8High
Golang Gopls
CVE-2026-42503
gopls by default communicates via pipe. However, -port and -listen flags are supported as means of debugging. If -listen is given a value without an explicit host (e.g. :8080), or -port is used, gopls will listen on 0.0.0.0. As a result, users might inadvertently cause gopls to bind 0.0.0.0. This can allow a malicious party on the same network to execute code arbitrarily via gopls.
What this means for your business
- It affects Golang Gopls. It matters if your company, or a supplier that handles your data, runs it.
- An attacker can use it from inside the same network, without a login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 0.2% chance of attack attempts being seen in the next 30 days, ranking above 13% of all known flaws.
What to do
- 1Check whether your company or your suppliers run Golang Gopls, 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.
Scoring
- CVSS
- 8.8 (v3.1)
- Vector
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H- Weakness
- CWE-1327
- Assigned by
- security@golang.org
Dates
- Published
- 2026-05-06
- Last modified
- 2026-09-18
- Sources
- NVD
Affected products
- Golang Gopls- 0.22.0
As listed in the NVD configuration data. Not a statement about your estate.