CVE-2026-12957

Code execution via trusted workspace configuration commands

Published Jun 23, 2026 · Updated Jun 23, 2026

Improper trust-boundary enforcement in Language Servers for AWS before 1.65.0 allows local users to execute arbitrary code via a workspace. The language-server runtime automatically executes commands defined in project-level configuration files after treating the workspace as trusted. Exploitation requires a user to open the crafted workspace and approve its trust prompt, after which the commands run on that user's host.

CVSS severity8.5
High
EPSS probability0.18%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper trust-boundary enforcement in Language Servers for AWS before 1.65.0 allows local users to execute arbitrary code via a workspace. The language-server runtime automatically executes commands defined in project-level configuration files after treating the workspace as trusted. Exploitation requires a user to open the crafted workspace and approve its trust prompt, after which the commands run on that user's host.

The record

CVE
CVE-2026-12957
Published
Jun 23, 2026
Updated
Jun 23, 2026
Vendor
Amazon Web Services
Product
Language Servers for AWS
Classifications
CWE-732, T1204.002
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 23, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 23, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <1.65.0

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Amazon Web Services · Language Servers for AWSversion=0 <1.65.0

Published CVSS scores

8.5Amazon Web ServicesCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
7.8Amazon Web ServicesCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-732Incorrect Permission Assignment for Critical Resource
T1204.002Malicious File

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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