gopls up to 0.21.x on Go binding to an unrestricted ip address

CVSS Meta Temp Score
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CTI Interest Score
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5.3$0-$5k0.00

Summaryinfo

A vulnerability was found in gopls up to 0.21.x on Go. It has been rated as problematic. Affected by this issue is some unknown functionality. The manipulation leads to binding to an unrestricted ip address. This vulnerability is documented as CVE-2026-42503. The attack requires being on the local network. There is not any exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in gopls up to 0.21.x on Go and classified as problematic. This issue affects an unknown function. The manipulation with an unknown input leads to a binding to an unrestricted ip address vulnerability. Using CWE to declare the problem leads to CWE-1327. The product assigns the address 0.0.0.0 for a database server, a cloud service/instance, or any computing resource that communicates remotely. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

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.

It is possible to read the advisory at go.dev. The identification of this vulnerability is CVE-2026-42503 since 04/28/2026. The exploitation is known to be easy. The attack needs to approached within the local network. The technical details are unknown and an exploit is not publicly available.

Upgrading to version 0.22.0 eliminates this vulnerability.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.5
VulDB Meta Temp Score: 5.3

VulDB Base Score: 5.5
VulDB Temp Score: 5.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Binding to an unrestricted ip address
CWE: CWE-1327 / CWE-284 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: gopls 0.22.0

Timelineinfo

04/28/2026 CVE reserved
05/06/2026 +8 days Advisory disclosed
05/06/2026 +0 days VulDB entry created
05/06/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: go.dev
Status: Confirmed

CVE: CVE-2026-42503 (🔒)
GCVE (CVE): GCVE-0-2026-42503
GCVE (VulDB): GCVE-100-361571

Entryinfo

Created: 05/06/2026 19:01
Changes: 05/06/2026 19:01 (52)
Complete: 🔍
Cache ID: 216::103

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