CVE-2026-126308 — CODER
HIGHCVE-2026-126308 is a high-severity (CVSS 7.7) CWE-201 vulnerability in coder coder. A fix is available — see the affected versions and patch details below.
The web dashboard in Coder 2.24.0 before 2.29.23, 2.30.0 before 2.34.14, 2.35.0 before 2.36.9, 2.37.0 before 2.37.6, and 2.38.0 before 2.38.2 replaces the $SESSION_TOKEN placeholder…
Description
The web dashboard in Coder 2.24.0 before 2.29.23, 2.30.0 before 2.34.14, 2.35.0 before 2.36.9, 2.37.0 before 2.37.6, and 2.38.0 before 2.38.2 replaces the $SESSION_TOKEN placeholder in external app URLs with a full-access API key without checking whether the app belongs to a sub-agent. Code running in a workspace can register a disguised sub-agent app with a custom protocol URL, so the owner's click sends their API key to an attacker-chosen destination.
Affected Products
codercodercodercodercodercodercodercodercodercodercodercoderDetection & mitigation playbook
Vendor / applianceDetect
Inventory every coder coder deployment and check each version against the affected-products list above.
Fix
Apply the coder coder security patch or hotfix for CVE-2026-126308 on the affected version, following the vendor advisory for your exact build.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands. Alongside that, restrict the management interface to trusted networks and apply the vendor's recommended configuration mitigations.
Frequently Asked Questions
Is CVE-2026-126308 being exploited in your environment?
Detect and block the exploit chain at execution, on systems you cannot patch yet.