Which versions of AWS RES are affected by EUVD-2026-42056?

AWS Research and Engineering Studio versions prior to 2026.06 allow authenticated cluster users to read sensitive files accessible by system administrators, including SSH keys and application…

How to fix or mitigate EUVD-2026-42056?

Within 24 hours: Identify all RES clusters in use and their versions via AWS API or CloudTrail; review API logs for Auth.GetUserPrivateKey calls to detect suspicious activity; document current SSH keys and secrets stored on cluster-manager instances. Within 7 days: Implement monitoring and alerting for Auth.GetUserPrivateKey API calls; rotate all SSH keys and secrets accessible from cluster-manager instances; restrict symbolic link creation in ~/.ssh directories via SELinux or AppArmor policies. Within 30 days: Schedule and execute upgrade to RES version 2026.06 or later in non-production environment first; coordinate with AWS for patch release timeline if not yet available; plan production deployment with change management.

AWS RES EUVD-2026-42056

Q: What is the CVSS score of EUVD-2026-42056?

EUVD-2026-42056 has a CVSS 4.0 base score of 7.1 (High). CVSS vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/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. EPSS exploitation probability: 0.4%.

| CVE-2026-14904 HIGH

Improper Link Resolution Before File Access (CWE-59)

2026-07-07 AMZN

GHSA-7xcj-pxq8-grgf

Information Disclosure AWS Res

7.1

CVSS 4.0 · Vendor: AMZN

Severity by source

Vendor (AMZN) PRIMARY

7.1 HIGH

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/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

vuln.today AI

6.5 MEDIUM

Network-reachable API needing an authenticated account (PR:L) and no user interaction; symlink read yields high confidentiality only, with no integrity or availability impact.

3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

4.0 AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N

Primary rating from Vendor (AMZN).

CVSS VectorVendor: AMZN

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Lifecycle Timeline

Analysis Generated

Jul 07, 2026 - 17:20 vuln.today

DescriptionCVE.org

AWS Research and Engineering Studio (RES) is an open-source solution that enables researchers and engineers to create and manage secure virtual desktops and computing resources on AWS.

Improper link resolution before file access issue (CWE-59) in the Auth.GetUserPrivateKey API. An authenticated remote user could read arbitrary files on the cluster-manager EC2 instance by replacing their SSH private key file (~/.ssh/id_rsa) with a symbolic link targeting any file on the host. Because the cluster-manager process runs as root, any file readable by root is exposed, including other users' SSH private keys and application configuration secrets.

It's recommended to upgrade to RES version 2026.06.

AnalysisAI

Arbitrary file disclosure in AWS Research and Engineering Studio (RES) prior to version 2026.06 allows an authenticated remote user to read any file readable by root on the cluster-manager EC2 instance. The Auth.GetUserPrivateKey API follows a user-controlled symbolic link at ~/.ssh/id_rsa, and because the cluster-manager process runs as root, an attacker can exfiltrate other users' SSH private keys and application secrets. No public exploit identified at time of analysis, and it is not listed in CISA KEV.

Technical ContextAI

AWS RES is an open-source AWS solution that provisions and manages secure virtual desktops and HPC-style computing resources on AWS, using a central cluster-manager component to broker authentication and user key material. The flaw is a CWE-59 (improper link resolution before file access / symlink following) weakness in the Auth.GetUserPrivateKey API: the service reads a user's SSH private key from a fixed path (~/.ssh/id_rsa) without validating that the path is a regular file rather than a symlink. Per the CPE cpe:2.3:a:aws:res:*, all RES versions before 2026.06 are affected. Because the reader process executes with root privileges, the classic symlink-follow primitive is amplified into an arbitrary root-readable file disclosure rather than being confined to the attacker's own files.

RemediationAI

Vendor-released patch: RES 2026.06 - upgrade the cluster-manager and RES environment to version 2026.06 as the primary fix, per the release at https://github.com/aws/res/releases/tag/2026.06 and the advisory at https://aws.amazon.com/security/security-bulletins/2026-053-aws/. If immediate upgrade is not possible, compensating controls include restricting or auditing which users hold authenticated RES accounts to shrink the attacker pool, monitoring or removing symlinks at ~/.ssh/id_rsa in user home directories on the cluster-manager, and rotating any SSH keys and application configuration secrets that could have been exposed to root-readable disclosure; note these controls reduce but do not eliminate the underlying symlink-follow flaw and may disrupt legitimate key management, so the version upgrade remains necessary.