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CVE-2021-26717

Published: Feb 18, 2021Updated: Nov 21, 2024 Sources: CVE List NVDNVD-CWE-noinfo
NVD MITRE
7.5CVSSHIGH
EPSS Score
2.2%
Top 20.0%
CISA KEV
Not in KEV
Exploits
1 Known
Remediation
Patch Available

Description

An issue was discovered in Sangoma Asterisk 16.x before 16.16.1, 17.x before 17.9.2, and 18.x before 18.2.1 and Certified Asterisk before 16.8-cert6. When re-negotiating for T.38, if the initial remote response was delayed just enough, Asterisk would send both audio and T.38 in the SDP. If this happened, and the remote responded with a declined T.38 stream, then Asterisk would crash.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:NI:NA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:NIntegrity
None
A:HAvailability
High
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Weaknesses

NVD-CWE-noinfo

Affected Products

asteriskdigiumCommunications
certified asteriskdigiumCommunications
n/an/a
digiumcommercialUSCommunicationsaka digium, asterisk

Exploitability

1 exploit source identified

Exploit details including PoC links, Metasploit modules, and scanner templates are available after registration.

View exploit details
Official Patch Available

References

http://packetstormsecurity.com/files/161471/Asterisk-Project-Security-Advisory-AST-2021-002.html
packetstormsecurity.com
http://seclists.org/fulldisclosure/2021/Feb/58
seclists.org
https://downloads.asterisk.org/pub/security/
downloads.asterisk.org
and 2 more references View all →

Timeline

Published
Feb 18, 2021
Last Updated
Nov 21, 2024

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