CVE-2026-42503 | Accidental binding to INADDR_ANY might lead to RCE in golang.org/x/tools/gopls

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.

Published: 2026-05-06 Last update: 2026-05-07 Assigner: [email protected] Source: [email protected]
NVD Status：Awaiting Analysis，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-42503 is rated Low Risk (36.8/100): CVSS High severity, with low exploitation likelihood (EPSS 0.02%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-42503

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-07 — 0.02% —

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-42503

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.8 3.1 HIGH
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:A)
Attacker has to be nearby on the network—same office, same link, that vibe—not the whole wide internet.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.8 5.9 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2026-42503

GitHub Security Advisory for CVE-2026-42503

GHSA-9344-f92h-vr44 · Severity: high — gopls by default communicates via pipe. However, -port and -listen flags are supported as means...

OS Trackers for CVE-2026-42503

vendor priority summary link
debian not yet assigned CVE-2026-42503 not yet assigned priority: Debian including 1 source packages (gopls), 3 status rows across 3 suites (forky, sid, trixie): open 3. https://security-tracker.debian.org/tracker/CVE-2026-42503
ubuntu medium CVE-2026-42503 medium priority: Ubuntu including 1 source packages (gopls), 5 status rows across 5 suites (jammy, noble, questing, resolute, upstream): needs-triage 3, DNE 2. https://ubuntu.com/security/CVE-2026-42503

Affected software / configurations for CVE-2026-42503

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2026-42503

cvelogic Threat Intelligence