Home/CVE/Asterisk is an open-source private branch exchange (PBX). Prior to versions 18.24.3, 20.9.3, and 21.4.3 of Asterisk and
CVE

CVE-2024-42491

Asterisk is an open-source private branch exchange (PBX). Prior to versions 18.24.3, 20.9.3, and 21.4.3 of Asterisk and

Asterisk is an open-source private branch exchange (PBX). Prior to versions 18.24.3, 20.9.3, and 21.4.3 of Asterisk and versions 18.9-cert12 and 20.7-cert2 of certified-asterisk, 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. To receive a patch, users should upgrade to one of the following versions: 18.24.3, 20.9.3, 21.4.3, certified-18.9-cert12, certified-20.7-cert2.

Two workarounds are available. Disable res_resolver_unbound by setting noload = res_resolver_unbound.so in modules.conf, or set rewrite_contact = yes on all PJSIP endpoints. NOTE: This may not be appropriate for all Asterisk configurations.

MEDIUM · CVSS 5.7 EPSS 0.00963
Monitor
  • No active-exploitation, high-EPSS, or public-exploit signals - routine patching cadence
Sigma rules0 YARA rules0
⬡

Weakness Classification

CWE-252Unchecked Return Value
CWE-476NULL Pointer Dereference
▤

Affected Products & Versions

5
sangoma asterisk< 18.24.3
sangoma asterisk>= 20.0.0 and < 20.9.3
sangoma asterisk>= 21.0.0 and <= 21.4.3
sangoma certified asterisk< 18.9
sangoma certified asteriskall versions
▣

Scoring & Timeline

5.7
MEDIUM · CVSS v3.1 · security-advisories@github.com
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD05 Sep 2024 · 06:15 PM
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H
SSVC triage · cisa-vulnrichment
Exploitation
none
Automatable
no
Technical impact
partial
SSVC asks the questions that actually drive patch urgency: is it being exploited, can attacks be automated, and how total is the impact.
🔗

References & Sources

7
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://github.com/asterisk/asterisk/commit/42a2f4ccfa2c7062a15063e765916b3332e34cc4Patch
https://github.com/asterisk/asterisk/commit/4f01669c7c41c9184f3cce9a3cf1b2ebf6201742Patch
https://github.com/asterisk/asterisk/commit/50bf8d4d3064930d28ecf1ce3397b14574d514d2Patch
https://github.com/asterisk/asterisk/commit/7a0090325bfa9d778a39ae5f7d0a98109e4651c8Patch
https://github.com/asterisk/asterisk/commit/a15050650abf09c10a3c135fab148220cd41d3a0Patch
https://github.com/asterisk/asterisk/security/advisories/GHSA-v428-g3cw-7hv9Vendor Advisory
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