Description
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.
Published: 2026-09-15
Score: 9.3 Critical
EPSS: < 1% Very Low
KEV: No
Impact: Remote Code Execution
Action: Immediate Patch
AI Analysis

Impact

The Iss HS256 JWT signing key that is identical in every installation. Attackers can generate a valid bearer token without authentication and then call the pbxapi/manager/originate API endpoint with the System application parameter. The Asterisk engine executes the supplied command string as the Asterisk user, giving the attacker arbitrary OS command execution on the host. Shadowserver observed active exploitation on 2026-09-09, confirming real‑world use.

Affected Systems

The vulnerability affects all deployments of Issabel Foundation’s Issabel Framework that use the pbxapi index.php file prior to the fix incorporated in commit b97dbaf0b71c1c36f841e672b664afbeb02773bd. Any installation that has not applied this patch is vulnerable.

Risk and Exploitability

The CVSS score of 9.3 reflects a high severity, and the EPSS score of 0.00521 (less than 1%) indicates a very low but nonzero exploitation probability. The vulnerability is not listed in the CISA KEV catalog. Attackers can remotely forge a bearer token without authentication and evolve it over HTTP or HTTPS to the pbxapi/manager/originate endpoint, causing Asterisk to run arbitrary OS commands as the Asterisk user. Because the flaw bypasses authentication, remote exploitation is straightforward.

Generated by OpenCVE AI on September 20, 2026 at 15:20 UTC.

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

  • Apply the Issabel Framework patch corresponding to commit b97dbaf0b71c1c36f841e672b, which removes the hard‑coded signing key and requires proper token generation.
  • Configure the framework to enforce JWT validation on all API requests and replace the default signing key with a unique, secure key per deployment.
  • Limit unauthenticated access to the pbxapi/manager/originate endpoint by configuring firewall rules or access‑control policies so that only trusted hosts or internal networks may send originate commands.

Generated by OpenCVE AI on September 20, 2026 at 15:20 UTC.

Tracking

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Advisories

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History

Thu, 17 Sep 2026 20:30:00 +0000

Type Values Removed Values Added
First Time appeared Issabel Foundation
Issabel Foundation issabel Framework
Vendors & Products Issabel Foundation
Issabel Foundation issabel Framework
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Tue, 15 Sep 2026 16:45:00 +0000

Type Values Removed Values Added
Description 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.
Title Issabel Framework Hard-coded JWT Key RCE via pbxapi/manager/originate
Weaknesses CWE-321
References
Metrics cvssV3_1

{'score': 9.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'}

cvssV4_0

{'score': 9.3, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N'}

Subscriptions

Issabel Foundation Issabel Framework
cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published:

Updated: 2026-09-17T19:27:44.069Z

Reserved: 2026-09-10T16:23:54.471Z

Link: CVE-2026-89026

cve-icon Vulnrichment

Updated: 2026-09-17T19:18:09.739Z

cve-icon NVD

Status : Deferred

Published: 2026-09-15T17:17:33.510

Modified: 2026-09-24T21:08:55.030

Link: CVE-2026-89026

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-09-20T15:30:17Z

Weaknesses
  • CWE-321

    Use of Hard-coded Cryptographic Key