CVE-2026-23740 Asterisk vulnerable to potential privilege escalation
An attacker can escalate privileges to root by exploiting world-writable directories used by Asterisk's coredumper for gdb files.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-23740?
CVE-2026-23740 is a vulnerability in asterisk, published on 6 Feb 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Official description
Asterisk is an open source private branch exchange and telephony toolkit. Prior to versions 20.7-cert9, 20.18.2, 21.12.1, 22.8.2, and 23.2.2, when ast_coredumper writes its gdb init and output files to a directory that is world-writable (for example /tmp), an attacker with write permission(which is all users on a linux system) to that directory can cause root to execute arbitrary commands or overwrite arbitrary files by controlling the gdb init file and output paths. This issue has been patched in versions 20.7-cert9, 20.18.2, 21.12.1, 22.8.2, and 23.2.2.
Weakness: CWE-427
Which versions are affected by CVE-2026-23740?
It affects 2 products.
Products include Sangoma Asterisk, Sangoma Certified Asterisk.
How do I fix CVE-2026-23740?
Apply the vendor's patch.
Is CVE-2026-23740 being exploited?
There is no known exploitation of CVE-2026-23740 in the wild and no public exploit code.
Other vulnerabilities in asterisk
- CVE-2024-57520 Path traversal in n/a
- CVE-2025-47779 Using malformed From header can forge identity with ";" or NULL in name portion
- CVE-2025-57767 Asterisk can crash from a specifically malformed Authorization header in an incoming SIP request
- CVE-2022-37325 Memory corruption in n/a
- CVE-2025-1131 Asterisk Unsafe Shell Sourcing in safe_asterisk Leads to Local Privilege Escalation
Sources
Also known as DEBIAN-CVE-2026-23740, GHSA-xpc6-x892-v83c, UBUNTU-CVE-2026-23740.