Description
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.
Published: 2026-07-08
Score: 7.7 High
EPSS: n/a
KEV: No
Impact: n/a
Action: n/a
AI Analysis

No analysis available yet.

Remediation

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Tracking

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Advisories
Source ID Title
Github GHSA Github GHSA GHSA-v54h-cp2w-9x4g Coder's session token leaked to arbitrary hosts via `coder open app` for external workspace apps
History

Wed, 08 Jul 2026 02:45:00 +0000

Type Values Removed Values Added
First Time appeared Coder
Coder coder
Vendors & Products Coder
Coder coder

Wed, 08 Jul 2026 01:00:00 +0000

Type Values Removed Values Added
Description 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.
Title Coder's session token leaked to arbitrary hosts via `coder open app` for external workspace apps
Weaknesses CWE-522
CWE-601
References
Metrics cvssV3_1

{'score': 7.7, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:N'}

Subscriptions

Coder Coder
cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-07-08T00:10:49.165Z

Reserved: 2026-06-16T21:59:57.017Z

Link: CVE-2026-55431

cve-icon Vulnrichment

No data.

cve-icon NVD

No data.

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-07-08T02:30:16Z

Weaknesses
  • CWE-522

    Insufficiently Protected Credentials

  • CWE-601

    URL Redirection to Untrusted Site ('Open Redirect')