8.5
HIGH CVSS 4.0
CVE-2026-12957
Arbitrary Code Execution in Language Servers for AWS
Description

Improper trust boundary enforcement in Language Servers for AWS before version 1.65.0 on all supported platforms may allow a for arbitrary code execution. If a local user opens a maliciously crafted workspace, any commands within the project configuration files may be automatically executed. This issue requires the user to trust the workspace when prompted. To remediate this issue, users should upgrade to Language Servers for AWS version 1.65.0 or higher.

INFO

Published Date :

June 23, 2026, 5:16 p.m.

Last Modified :

June 23, 2026, 7:36 p.m.

Remotely Exploit :

No

Source :

ff89ba41-3aa1-4d27-914a-91399e9639e5
Affected Products

The following products are affected by CVE-2026-12957 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 HIGH ff89ba41-3aa1-4d27-914a-91399e9639e5
CVSS 4.0 HIGH ff89ba41-3aa1-4d27-914a-91399e9639e5
CVSS 4.0 HIGH ff89ba41-3aa1-4d27-914a-91399e9639e5
Solution
Upgrade Language Servers for AWS to version 1.65.0 or higher to prevent arbitrary code execution.
  • Upgrade Language Servers for AWS to version 1.65.0 or later.
Public PoC/Exploit Available at Github

CVE-2026-12957 has a 3 public PoC/Exploit available at Github. Go to the Public Exploits tab to see the list.

References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-12957.

URL Resource
https://aws.amazon.com/security/security-bulletins/2026-047-aws/
https://github.com/aws/language-servers/security/advisories/GHSA-xhcr-j4j9-3gh7
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-12957 is associated with the following CWEs:

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Read-only Linux host checker for supply-chain incident response, including vulnerable kernel posture, risky module state, and known developer-tooling persistence indicators

JavaScript PowerShell

Updated: 1 day, 1 hour ago
1 stars 0 fork 0 watcher
Born at : May 13, 2026, 10:54 p.m. This repo has been linked 45 different CVEs too.

A curated timeline of real AI agent security incidents, breaches, and vulnerabilities (2024-2026). Every entry sourced and dated.

ai-agent-security ai-agents ai-security awesome-list cybersecurity llm-security mcp-security prompt-injection supply-chain-security adversarial-attacks agent-security agentic-ai ai-attacks ai-safety cve incident-response owasp red-team security-research vulnerability

Updated: 1 week, 4 days ago
29 stars 3 fork 3 watcher
Born at : April 7, 2026, 2:19 p.m. This repo has been linked 85 different CVEs too.

None

Updated: 2 weeks, 1 day ago
0 stars 0 fork 0 watcher
Born at : March 30, 2026, 11:20 a.m. This repo has been linked 1 different CVEs too.

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-12957 vulnerability anywhere in the article.

  • The Hacker News
GhostApproval Symlink Flaws Could Let Malicious Repos Run Code in AI Coding Agents

Researchers at Wiz found that a flaw in six popular AI coding assistants lets a booby-trapped code project quietly take control of a developer's computer. The assistant asks permission to edit one har ... Read more

Published Date: Jul 09, 2026 (4 days, 19 hours ago)
  • The Hacker News
Amazon Q Developer Flaw Could Let Malicious Repos Run Code via MCP Configs

A high-severity flaw in Amazon Q Developer let a malicious repository run commands and steal a developer's cloud credentials. The path was short: a developer opens the repo, trusts the workspace, and ... Read more

Published Date: Jun 26, 2026 (2 weeks, 3 days ago)

The following table lists the changes that have been made to the CVE-2026-12957 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by ff89ba41-3aa1-4d27-914a-91399e9639e5

    Jun. 23, 2026

    Action Type Old Value New Value
    Added Reference https://github.com/aws/language-servers/security/advisories/GHSA-xhcr-j4j9-3gh7
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Jun. 23, 2026

    Action Type Old Value New Value
    Added SSVC {'id': 'CVE-2026-12957', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-06-23T17:48:30.691572Z'}
  • New CVE Received by ff89ba41-3aa1-4d27-914a-91399e9639e5

    Jun. 23, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'Amazon Web Services', 'product': 'Language Servers for AWS', 'versions': [{'status': 'affected', 'version': '0', 'lessThan': '1.65.0', 'versionType': 'semver'}], 'defaultStatus': 'unaffected'}]
    Added Description Improper trust boundary enforcement in Language Servers for AWS before version 1.65.0 on all supported platforms may allow a for arbitrary code execution. If a local user opens a maliciously crafted workspace, any commands within the project configuration files may be automatically executed. This issue requires the user to trust the workspace when prompted. To remediate this issue, users should upgrade to Language Servers for AWS version 1.65.0 or higher.
    Added CVSS V4.0 AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CVSS V3.1 AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
    Added CWE CWE-732
    Added Reference https://aws.amazon.com/security/security-bulletins/2026-047-aws/
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.