SB2021072607 - Multiple vulnerabilities in Asterisk

Description

This security bulletin contains information about 2 secuirty vulnerabilities.

1) Resource management error (CVE-ID: CVE-2021-31878)

The 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.

2) Input validation error (CVE-ID: CVE-2021-32558)

The 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.

Remediation

Install update from vendor's website.

References

• https://downloads.asterisk.org/pub/security/AST-2021-007.html
• https://downloads.asterisk.org/pub/security/AST-2021-008.html