CVE-2026-23740: Asterisk vulnerable to potential privilege escalation

Published Feb 6, 2026
·
Updated

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 astcoredumper 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.

Affected Software

71 affected components
Asterisk Asterisk<20.7-cert9, <20.18.2, <21.12.1, <22.8.2, <23.2.2
Sangoma Certified Asterisk=13.13.0
Sangoma Certified Asterisk=13.13.0-cert1
Sangoma Certified Asterisk=13.13.0-cert1-rc1
Sangoma Certified Asterisk=13.13.0-cert1-rc2
Sangoma Certified Asterisk=13.13.0-cert1-rc3
Sangoma Certified Asterisk=13.13.0-cert1-rc4
Sangoma Certified Asterisk=13.13.0-cert2
Sangoma Certified Asterisk=13.13.0-cert3
Sangoma Certified Asterisk=13.13.0-rc1
Sangoma Certified Asterisk=13.13.0-rc2
Sangoma Certified Asterisk=16.8-cert1-rc1
Sangoma Certified Asterisk=16.8-cert1-rc2
Sangoma Certified Asterisk=16.8-cert1-rc3
Sangoma Certified Asterisk=16.8-cert1-rc4
Sangoma Certified Asterisk=16.8-cert1-rc5
Sangoma Certified Asterisk=16.8-cert10
Sangoma Certified Asterisk=16.8-cert11
Sangoma Certified Asterisk=16.8-cert12
Sangoma Certified Asterisk=16.8-cert13
Sangoma Certified Asterisk=16.8-cert14
Sangoma Certified Asterisk=16.8-cert4-rc1
Sangoma Certified Asterisk=16.8-cert4-rc2
Sangoma Certified Asterisk=16.8-cert4-rc3
Sangoma Certified Asterisk=16.8-cert4-rc4
Sangoma Certified Asterisk=16.8.0
Sangoma Certified Asterisk=16.8.0-cert1
Sangoma Certified Asterisk=16.8.0-cert10
Sangoma Certified Asterisk=16.8.0-cert11
Sangoma Certified Asterisk=16.8.0-cert12
Sangoma Certified Asterisk=16.8.0-cert2
Sangoma Certified Asterisk=16.8.0-cert3
Sangoma Certified Asterisk=16.8.0-cert4
Sangoma Certified Asterisk=16.8.0-cert5
Sangoma Certified Asterisk=16.8.0-cert6
Sangoma Certified Asterisk=16.8.0-cert7
Sangoma Certified Asterisk=16.8.0-cert8
Sangoma Certified Asterisk=16.8.0-cert9
Sangoma Certified Asterisk=18.9
Sangoma Certified Asterisk=18.9-cert1
Sangoma Certified Asterisk=18.9-cert1-rc1
Sangoma Certified Asterisk=18.9-cert10
Sangoma Certified Asterisk=18.9-cert11
Sangoma Certified Asterisk=18.9-cert12
Sangoma Certified Asterisk=18.9-cert13
Sangoma Certified Asterisk=18.9-cert14
Sangoma Certified Asterisk=18.9-cert15
Sangoma Certified Asterisk=18.9-cert16
Sangoma Certified Asterisk=18.9-cert2
Sangoma Certified Asterisk=18.9-cert3
Sangoma Certified Asterisk=18.9-cert4
Sangoma Certified Asterisk=18.9-cert5
Sangoma Certified Asterisk=18.9-cert6
Sangoma Certified Asterisk=18.9-cert7
Sangoma Certified Asterisk=18.9-cert8
Sangoma Certified Asterisk=18.9-cert8-rc1
Sangoma Certified Asterisk=18.9-cert8-rc2
Sangoma Certified Asterisk=18.9-cert9
Sangoma Certified Asterisk=20.7-cert1
Sangoma Certified Asterisk=20.7-cert1-rc1
Sangoma Certified Asterisk=20.7-cert1-rc2
Sangoma Certified Asterisk=20.7-cert2
Sangoma Certified Asterisk=20.7-cert3
Sangoma Certified Asterisk=20.7-cert4
Sangoma Certified Asterisk=20.7-cert5
Sangoma Certified Asterisk=20.7-cert6
Sangoma Certified Asterisk=20.7-cert7
Sangoma Asterisk<20.18.2
Sangoma Asterisk>=21.0.0<21.12.1
Sangoma Asterisk>=22.0.0<22.8.2
Sangoma Asterisk>=23.0.0<23.2.2

Event History

Feb 6, 2026
CVE Published
via MITRE·04:43 PM
Data Sourced
via MITRE·04:43 PM
DescriptionSeverityWeakness
Data Sourced
via NVD·05:16 PM
DescriptionSeverityWeaknessAffected Software
Jun 19, 58090
Event
via FIRST·03:55 PM
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Frequently Asked Questions

1

What is the severity of CVE-2026-23740?

CVE-2026-23740 has been rated as a medium severity privilege escalation vulnerability.

2

How do I fix CVE-2026-23740?

To fix CVE-2026-23740, upgrade to Asterisk versions 20.7-cert9, 20.18.2, 21.12.1, 22.8.2, or 23.2.2 or later.

3

What systems are affected by CVE-2026-23740?

CVE-2026-23740 affects Asterisk versions prior to 20.7-cert9, 20.18.2, 21.12.1, 22.8.2, and 23.2.2.

4

Is CVE-2026-23740 a remote exploitation risk?

CVE-2026-23740 is not a remote exploitation risk but allows for privilege escalation locally.

5

What does CVE-2026-23740 exploit?

CVE-2026-23740 exploits the world-writable permissions of directories used by ast_coredumper for output files.

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