Skip to main content
Live Webinar with SANS (June 25)— Agentic CTI Automation for Fun & ProfitRegister Free
Mallory
Back to vulnerabilities
Unrated

Arbitrary Code Execution in Language Servers for AWS Workspace Trust Handling

IdentifiersCVE-2026-12957CWE-501

CVE-2026-12957 is an arbitrary code execution vulnerability in Language Servers for AWS before version 1.65.0 on all supported platforms. The issue is caused by improper trust boundary enforcement in workspace handling. If a local user opens a maliciously crafted workspace and explicitly trusts that workspace when prompted, commands embedded in project configuration files may be automatically executed. The flaw is therefore tied to how the product treats trusted workspace content and allows project-supplied configuration to cross the intended trust boundary into command execution.

Share:
For your environment

Are you exposed to this one?

Mallory correlates every CVE against your assets, your vendors, and active adversary campaigns. Know which vulnerabilities matter for you, not just which ones are loud.

Start free trial
ANALYST BRIEF

Impact, mitigation & remediation

What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.

Impact

What an attacker gets, and what they’ve been doing with it.

Successful exploitation can result in arbitrary code execution in the context of the user running the IDE or tooling that uses Language Servers for AWS. Because commands from project configuration files may execute automatically, an attacker can potentially compromise confidentiality, integrity, and availability of the local environment accessible to that user, including execution of attacker-controlled programs, modification of local files, and disruption of developer workflows.

Mitigation

If you can’t patch tonight, do this now.

No vendor workaround is listed. Until patched versions are deployed, do not open untrusted or unverified workspaces, and do not mark a workspace as trusted unless its source and contents have been validated. Restrict use of shared or externally supplied project folders in affected IDE environments.

Remediation

Patch, then assume compromise.

Upgrade Language Servers for AWS to version 1.65.0 or later. Supporting advisory content also indicates AWS fixed related workspace-handling issues in later releases and recommends upgrading to the latest available Language Servers for AWS release and corresponding Amazon Q Developer IDE plugin releases where applicable. Any forked or derivative code should incorporate the vendor fixes.
PUBLIC EXPLOITS

Exploits

No public exploits tracked yet. Mallory keeps watching.

VALID 0 / 0 TOTALView more in app

No public exploit code observed for this vulnerability.

EXPOSURE SURFACE

Affected products & vendors

Products and vendors Mallory has correlated with this vulnerability. Open in Mallory to drill down to specific CPE configurations and version ranges.

VendorProductType
Amazon Web ServicesLanguage Servers For Awsapplication

Vendor-confirmed product mapping. Mallory continuously reconciles this list against your asset inventory.

ACTIVITY FEED

Recent activity

6 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.

6 SOURCESView more in app
What this page doesn’t show

The version that knows your environment.

This page is what’s public. Mallory adds the parts that aren’t: which of your assets are affected, which adversaries are exploiting it right now, which detections to deploy, and what to do tonight.
Start free trial
Exposure mapping

Query your assets running an affected version, and investigate the blast radius.

Threat actor evidence

Every observed campaign linking this CVE to a named adversary.

Associated malware

Malware families riding this exploit, with evidence and IOCs.

Detection signatures

YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.

Vendor-by-vendor mapping

Cross-references every affected SKU, including bundled OEM variants.

Social activity4

Community discussion across Reddit, Mastodon, and other social sources.

EXTERNAL REFERENCES
MITRE CVE
cve.org · CVE-2026-12957
NVD
nvd.nist.gov/vuln/detail/CVE-2026-12957
MITRE CWE · CWE-501
cwe.mitre.org