HighVulnerability

GHSA-xhcr-j4j9-3gh7: Language Servers for AWS Vulnerable to Arbitrary Code Execution

Source: GitHub Advisory(opens in a new tab)
Identifiers: CVE-2026-12957GHSA-xhcr-j4j9-3gh7
Published: September 24, 2026
Record updated: October 9, 2026

Affected: @aws/lsp-codewhisperer < 0.0.113
Fixed in: 0.0.113
released April 29, 2026, 148 days before disclosure
Known exploitation: Not listed in the CISA Known Exploited Vulnerabilities catalog at the last check.
EPSS: 0.2%

Summary

Language Servers for AWS, the runtime behind Amazon Q Developer's IDE plugins, contains an improper trust boundary enforcement flaw in versions <1.65.0. When a local user opens a maliciously crafted workspace and trusts it, commands defined in project-level configuration files may execute automatically, giving arbitrary code execution on the user's host.

Mitigation

Fixed in Language Servers for AWS version 1.65.0. Upgrade to the latest version and ensure any forked or derivative code incorporates the fix. No workarounds are available.

Details

Scores and exploitation

Patch available: Yes
EPSS: 0.2%Estimated probability that this CVE is exploited in the next 30 days, from the FIRST Exploit Prediction Scoring System. Read on November 9, 2026.
Disclosure date: September 24, 2026

Affected

Packages: @aws/lsp-codewhisperer@< 0.0.113 (fixed: 0.0.113)
Vendors: Amazon

Classification

Attack type: Other
Attack sophistication: Moderate
AI component targeted: Plugin
Impact: Confidentiality,
Integrity,
Availability
Labels: security,
industry

How this record was produced

Summaries, mitigations and labels on this page are generated automatically from the source. The linked source is authoritative.

Original source: https://github.com/advisories/GHSA-xhcr-j4j9-3gh7

First tracked: September 24, 2026 at 08:01 PM ET, from GitHub Advisory Database

Classifier: claude-haiku-5-5, prompt v4

Classifier confidence: 85% (self-assessed)

Summary

Mitigation

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