Improper Resource Shutdown or Release - CVE-2021-26906
Published: February 18, 2021 / Updated: February 26, 2021
Vulnerability identifier: #VU50967
CSH Severity: Medium
CVSSv4.0: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2021-26906
CWE-ID: CWE-404
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerable software:
Software vendor:
Description
The vulnerability allows a remote non-authenticated attacker to perform a denial of service (DoS) attack.
An issue was discovered in res_pjsip_session.c in Digium Asterisk through 13.38.1; 14.x, 15.x, and 16.x through 16.16.0; 17.x through 17.9.1; and 18.x through 18.2.0, and Certified Asterisk through 16.8-cert5. An SDP negotiation vulnerability in PJSIP allows a remote server to potentially crash Asterisk by sending specific SIP responses that cause an SDP negotiation failure.
Remediation
Install update from vendor's website.
External links
- http://packetstormsecurity.com/files/161477/Asterisk-Project-Security-Advisory-AST-2021-005.html
- http://seclists.org/fulldisclosure/2021/Feb/61
- https://downloads.asterisk.org/pub/security/
- https://downloads.asterisk.org/pub/security/AST-2021-005.html
- https://issues.asterisk.org/jira/browse/ASTERISK-29196