CVE-2026-42503: golang.org/x/tools/gopls · Binding to an Unrestricted IP Address
Affects golang.org/x/tools/goplsSource CVE Database V5
Not known to be exploited · CVSS 8.8 High : upgrade to 0.22.0 soon.
Data as of 30 Oct 2026, 11:52 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 11% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 0.22.0
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 6 May 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Upgrade golang.org/x/tools/gopls to 0.22.0.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| golang.org/x/toolsgolang.org/x/tools/gopls | Affected
| Fixed in
|
Gogolang.org/x/tools/goplspkg:golang/golang.org/x/tools/goplsOther threats | Affected
| Fixed in– |
Gogolang.org/x/tools/goplspkg:golang/golang.org/x/tools/goplsOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
If you cannot patch yet, users should avoid using the -listen flag without specifying an explicit host or the -port flag to prevent gopls from binding to all interfaces. Restrict network access to the machine running gopls to trusted users only.
Description
The golang.org/x/tools/gopls language server has a vulnerability where it may bind to the unrestricted IP address 0.0.0.0 when started with certain debugging flags (-listen without explicit host or -port). This behavior can expose the service to network attackers on the same network, potentially allowing arbitrary code execution. The vulnerability is rated high severity with a CVSS score of 8.8. Users should be cautious when using these flags and avoid binding gopls to all network interfaces unless necessary.