CVE-2024-42365: Asterisk allows `Write=originate` as sufficient permissions for code execution / `System()` dialplan

Severity: high (CVSS 8.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 4.7% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2024-08-08 · updated 2026-06-17
Weakness: CWE-267

Description

Asterisk is an open source private branch exchange (PBX) and telephony toolkit. Prior to asterisk versions 18.24.2, 20.9.2, and 21.4.2 and certified-asterisk versions 18.9-cert11 and 20.7-cert2, an AMI user with `write=originate` may change all configuration files in the `/etc/asterisk/` directory. This occurs because they are able to curl remote files and write them to disk, but are also able to append to existing files using the `FILE` function inside the `SET` application. This issue may result in privilege escalation, remote code execution and/or blind server-side request forgery with arbitrary protocol. Asterisk versions 18.24.2, 20.9.2, and 21.4.2 and certified-asterisk versions 18.9-cert11 and 20.7-cert2 contain a fix for this issue.

Affected products

Asterisk: before 18.24.2; from 19.0.0 before 20.9.1; 21.4.0 — fixed in 18.24.2, 20.9.1
asterisk Certified Asterisk: 13.13.0, 13.13.0-cert1, 13.13.0-cert1-rc1, 13.13.0-cert1-rc2, 13.13.0-cert1-rc3, 13.13.0-cert1-rc4 (+47)

How to fix

Upgrade to a fixed version: Asterisk 18.24.2, 20.9.1. Check the vendor advisory for mitigations.

References

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