High severity · published Apr 21, 2026
CVE-2026-40520
FreePBX api module Command Injection via GraphQL
8.8
CVSS
1.4%
EPSS
No
On KEV
Description
FreePBX api module version 17.0.8 and prior contain a command injection vulnerability in the initiateGqlAPIProcess() function where GraphQL mutation input fields are passed directly to shell_exec() without sanitization or escaping. An authenticated user with a valid bearer token can send a GraphQL moduleOperations mutation with backtick-wrapped commands in the module field to execute arbitrary commands on the underlying host as the web server user.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.4% · higher than 72% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AP
api · FreePBX
through 17.0.8 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-40520
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-40520
Product
https://github.com/FreePBX/api/blob/5f194e39a47e5481e8947f9694304d32724175f6/Api.class.php#L546C1-L554C3
Product
https://github.com/FreePBX/api/blob/5f194e39a47e5481e8947f9694304d32724175f6/ApiGqlHelper.class.php#L34C1-L36C136
Patch
https://github.com/FreePBX/api/commit/5f194e39a47e5481e8947f9694304d32724175f6
Third Party Advisory
https://www.vulncheck.com/advisories/freepbx-api-module-command-injection-via-graphql
More from api
7.5
CVE-2025-55210
FreePBX API has a Privilege Escalation Error in GraphQL Allowing Authenticated Users to Access Additional Scopes