CVE-2026-55431

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.

CVSS v3 7.7 HIGH

7.7^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.3 / Impact : 5.8

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/coder/coder/pull/26146	Issue Tracking Patch
https://github.com/coder/coder/releases/tag/v2.29.17	Release Notes
https://github.com/coder/coder/releases/tag/v2.32.7	Release Notes
https://github.com/coder/coder/releases/tag/v2.33.8	Release Notes
https://github.com/coder/coder/releases/tag/v2.34.2	Release Notes
https://github.com/coder/coder/security/advisories/GHSA-v54h-cp2w-9x4g	Patch Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:coder:coder::::::go::*
	cpe:2.3:a:coder:coder::::::go::*
	cpe:2.3:a:coder:coder::::::go::*
	cpe:2.3:a:coder:coder::::::go::*

History

No history.

Information

Published : 2026-07-08 01:16

Updated : 2026-07-08 19:42

NVD link : CVE-2026-55431

Mitre link : CVE-2026-55431

CVE.ORG link : CVE-2026-55431

JSON object : View

Products Affected

coder

coder

CWE

CWE-522

Insufficiently Protected Credentials

CWE-601

URL Redirection to Untrusted Site ('Open Redirect')

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