9.8
CRITICAL CVSS 3.1
CVE-2026-89026
Issabel Framework Hard-coded JWT Key RCE via pbxapi/manager/originate
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.

INFO

Published Date :

Sept. 15, 2026, 5:17 p.m.

Last Modified :

Sept. 15, 2026, 5:17 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-89026 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 CRITICAL 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 3.1 CRITICAL MITRE-CVE
CVSS 3.1 CRITICAL [email protected]
CVSS 4.0 CRITICAL 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 4.0 CRITICAL [email protected]
Solution
Update the Issabel Framework to remove the hard-coded JWT signing key and prevent token forgery.
  • Update the Issabel Framework to the latest version.
  • Apply the commit b97dbaf to address the hard-coded key.
  • Remove the hard-coded HS256 JWT signing key.
  • Implement a unique signing key per installation.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-89026.

URL Resource
https://github.com/IssabelFoundation/framework/commit/b97dbaf0b71c1c36f841e672b664afbeb02773bd
https://www.vulncheck.com/advisories/issabel-pbx-hard-coded-jwt-key-rce-via-pbxapi-manager-originate
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-89026 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-89026 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-89026 vulnerability anywhere in the article.

  • The Hacker News
Attackers Exploit Issabel Framework Flaw Enabling Unauthenticated OS Command Execution

A critical security flaw in Issabel Framework, a web-based framework for the open-source unified communications PBX software, has come under active exploitation. The vulnerability in question is CVE-2 ... Read more

Published Date: Sep 16, 2026 (5 hours, 3 minutes ago)

The following table lists the changes that have been made to the CVE-2026-89026 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Sep. 15, 2026

    Action Type Old Value New Value
    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.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    Added CWE CWE-321
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/89xxx/CVE-2026-89026.json">CVE-2026-89026</a>
    Added Reference https://github.com/IssabelFoundation/framework/commit/b97dbaf0b71c1c36f841e672b664afbeb02773bd
    Added Reference https://www.vulncheck.com/advisories/issabel-pbx-hard-coded-jwt-key-rce-via-pbxapi-manager-originate
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.