CVE-2026-42503
Description
A flaw was found in gopls. When started with -listen using a hostless address (for example :8080) or with -port, the language server binds to 0.0.0.0 instead of localhost, exposing the debug interface to the local network and allowing arbitrary code execution by a malicious party on the same network.
Statement
gopls is vulnerable to arbitrary code execution when debug flags cause it to listen on all interfaces. Using -listen without an explicit host or the -port flag binds 0.0.0.0, so any attacker on the same network can reach the gopls debug endpoint and run code in the developer context. Red Hat exposure is in hummingbird golang1.25 and golang1.26 toolchains and the trivy component that bundles gopls for Go language support.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 8.8 | N/A | 8.8 |
| Attack Vector | Adjacent Network | N/A | Adjacent Network |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | None | N/A | None |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | High | N/A | High |
| Integrity Impact | High | N/A | High |
| Availability Impact | High | N/A | High |
Vector
Red Hat: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
cve.org: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Amplification
Frequently Asked Questions
Not sure what something means? Check out our Security Glossary.
Want to get errata notifications? Sign up here.
