CVE-2026-89026
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.
What this means for your business
- An attacker can use it remotely, over a network, without a login, and without anyone at your company clicking anything.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
Not sure if your company is exposed?
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Scoring
- CVSS
- 9.8 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H- CVSS v4
- 9.3
- Weakness
- CWE-321
- Assigned by
- disclosure@vulncheck.com
Dates
- Published
- 2026-09-15
- Last modified
- 2026-09-15
- Sources
- NVD
Coverage
- Attackers Exploit Issabel Framework Flaw Enabling Unauthenticated OS Command ExecutionThe Hacker News · 2026-09-16