PT-2024-5928 · Sangoma+2 · Certified Asterisk+3

Mbradeen · Published 2024-09-05 · Updated 2025-08-26 · CVE-2024-42491

Positive Technologies (AI Summary)

CVSS v2.0

6.8

Medium

Base vector

AV:N/AC:L/Au:S/C:N/I:N/A:C

Name of the Vulnerable Software and Affected Versions Asterisk versions prior to 18.24.3, 20.9.3, and 21.4.3 Certified Asterisk versions prior to 18.9-cert12 and 20.7-cert2

Description The issue is related to errors in sending SIP requests to URIs. If Asterisk attempts to send a SIP request to a URI whose host portion starts with .1 or [.1], and res resolver unbound is loaded, Asterisk will crash with a SEGV. This can allow a remote attacker to cause a denial of service and termination of the service.

Recommendations For versions prior to 18.24.3, 20.9.3, and 21.4.3 of Asterisk, upgrade to one of the following versions: 18.24.3, 20.9.3, or 21.4.3. For versions prior to 18.9-cert12 and 20.7-cert2 of Certified Asterisk, upgrade to one of the following versions: certified-18.9-cert12 or certified-20.7-cert2. As a temporary workaround, disable res resolver unbound by setting noload = res resolver unbound.so in modules.conf. Alternatively, set rewrite contact = yes on all PJSIP endpoints, but note that this may not be appropriate for all Asterisk configurations.

Exploit

Fix

Unchecked Return Value

NULL Pointer Dereference

Weakness Enumeration

CWE-252

CWE-476

Related Identifiers

ALT-PU-2025-2429

ALT-PU-2025-2613

BDU:2024-06734

CVE-2024-42491

DLA-3925-1

GHSA-V428-G3CW-7HV9

Affected Products

Alt Linux

Asterisk

Certified Asterisk

Red Os

References · 28

• 🔥 https://github.com/rapid7/metasploit-framework/blob/master/modules/exploits/linux/misc/asterisk_ami_originate_auth_rce.rb · Exploit
• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/42xxx/CVE-2024-42491.json · Exploit
• https://github.com/asterisk/asterisk/commit/7a0090325bfa9d778a39ae5f7d0a98109e4651c8 · Patch
• https://github.com/asterisk/asterisk/commit/42a2f4ccfa2c7062a15063e765916b3332e34cc4 · Patch
• https://github.com/asterisk/asterisk/commit/4f01669c7c41c9184f3cce9a3cf1b2ebf6201742 · Patch
• https://github.com/asterisk/asterisk/security/advisories/GHSA-v428-g3cw-7hv9 · Vendor Advisory
• https://github.com/asterisk/asterisk/commit/a15050650abf09c10a3c135fab148220cd41d3a0 · Patch
• https://github.com/asterisk/asterisk/commit/50bf8d4d3064930d28ecf1ce3397b14574d514d2 · Patch
• https://osv.dev/vulnerability/UBUNTU-CVE-2024-42491 · Vendor Advisory
• https://osv.dev/vulnerability/DLA-3925-1 · Vendor Advisory
• http://repo.red-soft.ru/redos/7.3c/x86_64/updates · Vendor Advisory
• https://bdu.fstec.ru/vul/2024-06734 · Security Note
• https://ubuntu.com/security/CVE-2024-42491 · Vendor Advisory
• https://osv.dev/vulnerability/ALPINE-CVE-2024-42491 · Vendor Advisory
• https://osv.dev/vulnerability/CVE-2024-42491 · Vendor Advisory