CVE-2026-55431

What it is

Coder allows organizations to provision remote development environments via Terraform. Prior to versions 2.29.7, 2.32.7, 2.33.8, and 2.34.2, `coder open app` opens external workspace-app URLs without validating the scheme or host. When an external app URL contains the `$SESSION_TOKEN` placeholder the CLI replaces it with the user's real session token before handing the URL to the OS open handler. Practical exploitation requires the victim to run `coder open app` against a workspace whose external app definition the attacker controls. Only a malicious template author can control external app URLs. The fix in versions 2.29.7, 2.32.7, 2.33.8, and 2.34.2 applies a URL-scheme allowlist in the CLI and limits `$SESSION_TOKEN` substitution to trusted destinations like the web frontend. As a workaround, avoid running `coder open app` for untrusted workspaces.

At a glance

Exploitability

Can be exploited over the network with a low-privilege account, but needs a user to act. High risk of data exposure, data tampering.

Exploit odds

0.3% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2026-07-08 01:16 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-07-08 19:42 UTC Last updatedMost recent change to the record

Details

Published

2026-07-08 01:16 UTC

Last modified

2026-07-08 19:42 UTC

Exploit probability

0.3% · EPSS, next 30 days

Weakness

CWE-522

Record status

Analyzed

Affected

• Coder < 2.29.17
• Coder < 2.32.7
• Coder < 2.33.8
• Coder < 2.34.2

Attack profile CVSS 3.1 · 7.7

Attack vector

Network

Complexity

High

Privileges needed

Low

User interaction

Required

Scope

Changed

Confidentiality

High

Integrity

High

Availability

None