CVE-2026-89026: Issabel Framework Hard-coded JWT Key RCE via pbxapi/manager/originate
The Issabel Framework, the web framework supporting Issabel PBX software, before commit b97dbaf contains a hard-coded HS256 JWT signing key in the pbxapi index.php file that is identical across every installation, allowing unauthenticated remote attackers to forge valid bearer tokens. Attackers can use the forged token to call the manager originate endpoint with the System application parameter, causing Asterisk to execute arbitrary OS commands as the Asterisk user. Exploitation evidence was first observed by the Shadowserver Foundation on 2026-09-09.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
Issabel Framework (pbxapi/index.php)to a version that resolves this vulnerability.Patch commit b97dbaf - Compensating control
Restrict network access to the Asterisk manager originate endpoint (pbxapi/manager/originate) so unauthenticated remote attackers cannot reach it.
Event History
Frequently Asked Questions
Who can exploit this issue?
Any unauthenticated remote attacker able to reach the affected Issabel Framework pbxapi endpoint can forge bearer tokens because the HS256 JWT signing key is identical across installations.
What access or interaction does exploitation require?
Exploitation requires network access to the affected endpoint only. It does not require prior authentication, privileges, or user interaction.
What is the impact of a successful attack?
An attacker can invoke the manager originate endpoint with the System application parameter, causing Asterisk to execute arbitrary operating-system commands as the Asterisk user.
How can I determine whether my installation is affected?
Installations whose Issabel Framework version predates commit b97dbaf are affected. Review the framework source or deployed version history to determine whether commit b97dbaf0b71c1c36f841e672b664afbeb02773bd is present.
Is exploitation occurring in the wild?
Yes. The Shadowserver Foundation first observed exploitation evidence on 2026-09-09.