CVE-2024-42491
A malformed Contact or Record-Route URI in an incoming SIP request can cause Asterisk to crash when res_resolver_unbound is used
Description
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.
INFO
Published Date :
Sept. 5, 2024, 6:15 p.m.
Last Modified :
Aug. 26, 2025, 5:47 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2024-42491
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | [email protected] |
Solution
- Upgrade the asterisk packages.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2024-42491.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2024-42491 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2024-42491
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2024-42491 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2024-42491 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
Aug. 26, 2025
Action Type Old Value New Value Added CPE Configuration OR *cpe:2.3:a:sangoma:asterisk:*:*:*:*:*:*:*:* versions up to (excluding) 18.24.3 *cpe:2.3:a:sangoma:asterisk:*:*:*:*:*:*:*:* versions from (including) 20.0.0 up to (excluding) 20.9.3 *cpe:2.3:a:sangoma:asterisk:*:*:*:*:*:*:*:* versions from (including) 21.0.0 up to (including) 21.4.3 Added CPE Configuration OR *cpe:2.3:a:sangoma:certified_asterisk:18.9:cert2:*:*:*:*:*:* *cpe:2.3:a:sangoma:certified_asterisk:18.9:cert1:*:*:*:*:*:* *cpe:2.3:a:sangoma:certified_asterisk:*:*:*:*:*:*:*:* versions up to (excluding) 18.9 *cpe:2.3:a:sangoma:certified_asterisk:18.9:cert3:*:*:*:*:*:* *cpe:2.3:a:sangoma:certified_asterisk:18.9:cert4:*:*:*:*:*:* *cpe:2.3:a:sangoma:certified_asterisk:18.9:cert5:*:*:*:*:*:* *cpe:2.3:a:sangoma:certified_asterisk:18.9:-:*:*:*:*:*:* *cpe:2.3:a:sangoma:certified_asterisk:18.9:cert10:*:*:*:*:*:* *cpe:2.3:a:sangoma:certified_asterisk:18.9:cert11:*:*:*:*:*:* *cpe:2.3:a:sangoma:certified_asterisk:18.9:cert1-rc1:*:*:*:*:*:* *cpe:2.3:a:sangoma:certified_asterisk:18.9:cert6:*:*:*:*:*:* *cpe:2.3:a:sangoma:certified_asterisk:18.9:cert7:*:*:*:*:*:* *cpe:2.3:a:sangoma:certified_asterisk:18.9:cert8:*:*:*:*:*:* *cpe:2.3:a:sangoma:certified_asterisk:18.9:cert8-rc1:*:*:*:*:*:* *cpe:2.3:a:sangoma:certified_asterisk:18.9:cert8-rc2:*:*:*:*:*:* *cpe:2.3:a:sangoma:certified_asterisk:18.9:cert9:*:*:*:*:*:* *cpe:2.3:a:sangoma:certified_asterisk:20.7:cert1:*:*:*:*:*:* *cpe:2.3:a:sangoma:certified_asterisk:20.7:cert1-rc1:*:*:*:*:*:* *cpe:2.3:a:sangoma:certified_asterisk:20.7:cert1-rc2:*:*:*:*:*:* *cpe:2.3:a:sangoma:certified_asterisk:20.7:cert2:*:*:*:*:*:* Added Reference Type GitHub, Inc.: https://github.com/asterisk/asterisk/security/advisories/GHSA-v428-g3cw-7hv9 Types: Vendor Advisory Added Reference Type GitHub, Inc.: https://github.com/asterisk/asterisk/commit/42a2f4ccfa2c7062a15063e765916b3332e34cc4 Types: Patch Added Reference Type GitHub, Inc.: https://github.com/asterisk/asterisk/commit/4f01669c7c41c9184f3cce9a3cf1b2ebf6201742 Types: Patch Added Reference Type GitHub, Inc.: https://github.com/asterisk/asterisk/commit/50bf8d4d3064930d28ecf1ce3397b14574d514d2 Types: Patch Added Reference Type GitHub, Inc.: https://github.com/asterisk/asterisk/commit/7a0090325bfa9d778a39ae5f7d0a98109e4651c8 Types: Patch Added Reference Type GitHub, Inc.: https://github.com/asterisk/asterisk/commit/a15050650abf09c10a3c135fab148220cd41d3a0 Types: Patch -
CVE Received by [email protected]
Sep. 05, 2024
Action Type Old Value New Value Added Description 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. Added Reference GitHub, Inc. https://github.com/asterisk/asterisk/security/advisories/GHSA-v428-g3cw-7hv9 [No types assigned] Added Reference GitHub, Inc. https://github.com/asterisk/asterisk/commit/42a2f4ccfa2c7062a15063e765916b3332e34cc4 [No types assigned] Added Reference GitHub, Inc. https://github.com/asterisk/asterisk/commit/4f01669c7c41c9184f3cce9a3cf1b2ebf6201742 [No types assigned] Added Reference GitHub, Inc. https://github.com/asterisk/asterisk/commit/50bf8d4d3064930d28ecf1ce3397b14574d514d2 [No types assigned] Added Reference GitHub, Inc. https://github.com/asterisk/asterisk/commit/7a0090325bfa9d778a39ae5f7d0a98109e4651c8 [No types assigned] Added Reference GitHub, Inc. https://github.com/asterisk/asterisk/commit/a15050650abf09c10a3c135fab148220cd41d3a0 [No types assigned] Added CWE GitHub, Inc. CWE-252 Added CWE GitHub, Inc. CWE-476 Added CVSS V3.1 GitHub, Inc. AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H