Multiple vulnerabilities in Asterisk
| Risk | Medium |
| Patch available | YES |
| Number of vulnerabilities | 2 |
| CVE-ID | CVE-2021-31878 CVE-2021-32558 |
| CWE-ID | CWE-399 CWE-20 |
| Exploitation vector | Network |
| Public exploit | N/A |
| Vulnerable software Subscribe |
Asterisk Open Source Server applications / Conferencing, Collaboration and VoIP solutions Certified Asterisk Server applications / Conferencing, Collaboration and VoIP solutions |
| Vendor | Digium (Linux Support Services) |
Security Bulletin
This security bulletin contains information about 2 vulnerabilities.
1) Resource management error
EUVDB-ID: #VU55286
Risk: Low
CVSSv3.1: 3.8 [CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:U/RL:O/RC:C]
CVE-ID: CVE-2021-31878
CWE-ID:
CWE-399 - Resource Management Errors
Exploit availability: No
DescriptionThe vulnerability allows a remote user to perform a denial of service (DoS) attack.
The vulnerability exists due to improper management of internal resources within the application in PJSIP channel driver in res_pjsip_session.c. A remote user can send a re-INVITE message without SDP after Asterisk has sent a BYE request and perform a denial of service (DoS) attack.
Install updates from vendor's website.
Vulnerable software versionsAsterisk Open Source: 16.17.0 rc1 - 18.5.0 rc1
External linkshttp://downloads.asterisk.org/pub/security/AST-2021-007.html
Q & A
Can this vulnerability be exploited remotely?
Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.
Is there known malware, which exploits this vulnerability?
No. We are not aware of malware exploiting this vulnerability.
2) Input validation error
EUVDB-ID: #VU55294
Risk: Medium
CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]
CVE-ID: CVE-2021-32558
CWE-ID:
CWE-20 - Improper input validation
Exploit availability: No
DescriptionThe vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to insufficient validation of user-supplied input within the IAX2 channel driver chan_iax2.c. A remote attacker can send a packet that contains an unsupported media format and perform a denial of service (DoS) attack.
Install updates from vendor's website.
Vulnerable software versionsAsterisk Open Source: 13.23.0 rc1 - 18.5.0 rc1
Certified Asterisk: 16.3-cert1 - 16.8-cert9
External linkshttp://downloads.asterisk.org/pub/security/AST-2021-008.html
Q & A
Can this vulnerability be exploited remotely?
Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.
Is there known malware, which exploits this vulnerability?
No. We are not aware of malware exploiting this vulnerability.
