CVE-2026-12958: AWS Language Servers arbitrary file write via symlink validation bypass

CVE-2026-12958 · Severity: high · CVSS 7.8 · Published 2026-06-23

Language Servers for AWS, which provides AI-powered coding assistance for various development environments, contains a vulnerability that could allow unauthorized file modifications. If a developer opens a specially crafted project folder containing malicious links, the software may write data to sensitive files outside of the intended project area. This could lead to the corruption of system files or the placement of malicious code on the user's computer.

Vendors: Amazon Web Services, npm.

Quick answers

Is CVE-2026-12958 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-12958 being exploited in the wild.
How severe is CVE-2026-12958?
High severity, with a CVSS score of 7.8, published 23 June 2026.
Which products and versions are affected?
Amazon Web Services Amazon Q Developer for Eclipse < 2.7.4; Amazon Web Services Amazon Q Developer for JetBrains < 4.3; Amazon Web Services Amazon Q Developer for Visual Studio Code < 2.20; Amazon Web Services AWS Toolkit with Amazon Q for Visual Studio < 1.94.0.0; and 2 more.
Is there a fix for CVE-2026-12958?
Yes. @aws/lsp-codewhisperer (npm): upgrade to 0.0.117 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-12958 attacked?
It is attacked with local access, in a software library.
Am I affected by CVE-2026-12958?
Check whether you run Amazon Web Services Amazon Q Developer for Eclipse, Amazon Web Services Amazon Q Developer for JetBrains, Amazon Web Services Amazon Q Developer for Visual Studio Code or one of the others listed at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • @aws/lsp-codewhisperer (npm): upgrade to 0.0.117 or later
    npm install @aws/lsp-codewhisperer@0.0.117

Technical details

A symbolic link (symlink) following vulnerability (CWE-61) exists in Language Servers for AWS before version 1.69.0. The issue stems from a lack of proper validation for symlinks within a workspace, which can be exploited if a local user is enticed into opening a maliciously crafted workspace. An attacker can use a symlink that resolves to a path outside the workspace trust boundary to achieve arbitrary file writes on the local filesystem. This vulnerability affects several IDE plugins that bundle the language server, including Amazon Q Developer for VS Code, JetBrains, Eclipse, and Visual Studio. Users should upgrade to Language Servers for AWS version 1.69.0 or the corresponding updated IDE plugin versions.

Affected products

  • Amazon Web Services Language Servers for AWS < 1.69.0
  • Amazon Web Services Amazon Q Developer for Visual Studio Code < 2.20
  • Amazon Web Services Amazon Q Developer for JetBrains < 4.3
  • Amazon Web Services Amazon Q Developer for Eclipse < 2.7.4
  • Amazon Web Services AWS Toolkit with Amazon Q for Visual Studio < 1.94.0.0

Identifiers

  • CVE-2026-12958
  • GHSA-6v3r-4p5c-mrp5

Timeline

  • 2026-06-23: advisory: AWS security bulletin 2026-047-AWS published
  • 2026-06-23: disclosed: CVE-2026-12958 published to NVD

References

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