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CVE-2021-26713

Published: Feb 19, 2021Updated: Nov 21, 2024 Sources: CVE List NVDCWE-787
NVD MITRE
6.5CVSSMEDIUM
EPSS Score
1.8%
Top 23.7%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available

Description

A stack-based buffer overflow in res_rtp_asterisk.c in Sangoma Asterisk before 16.16.1, 17.x before 17.9.2, and 18.x before 18.2.1 and Certified Asterisk before 16.8-cert6 allows an authenticated WebRTC client to cause an Asterisk crash by sending multiple hold/unhold requests in quick succession. This is caused by a signedness comparison mismatch.

CVSS Vector Breakdown

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

CWE-787

Affected Products

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

Attack Graph

Products CVE Techniques Tactics

Click technique nodes to view MITRE ATT&CK details. Scroll to zoom, drag to pan.

Exploitability

Official Patch Available

MITRE ATT&CK

2 techniques
Initial Access
Privilege Escalation
View detailed technique mapping

References

https://downloads.asterisk.org/pub/security/
downloads.asterisk.org
https://downloads.asterisk.org/pub/security/AST-2021-004.html
downloads.asterisk.org
https://issues.asterisk.org/jira/browse/ASTERISK-29205
issues.asterisk.org

Timeline

Published
Feb 19, 2021
Last Updated
Nov 21, 2024

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