High severity · published Apr 29, 2021
CVE-2021-1501
A vulnerability in the SIP inspection engine of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated,…
7.5
CVSS
1.4%
EPSS
No
On KEV
Description
A vulnerability in the SIP inspection engine of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a crash and reload of an affected device, resulting in a denial of service (DoS) condition.The vulnerability is due to a crash that occurs during a hash lookup for a SIP pinhole connection. An attacker could exploit this vulnerability by sending crafted SIP traffic through an affected device. A successful exploit could allow the attacker to cause a crash and reload of the affected device.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.4% · higher than 71% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AS
Adaptive Security Appliance Software · Cisco
9.8 before 9.8.4.34; 9.9 before 9.9.2.85; 9.10 before 9.12.4.18; 9.13 before 9.13.1.21; 9.14 before 9.14.2.13; 9.15 before 9.15.1.15 · source: NVD
SF
Secure Firewall Threat Defense · Cisco
6.2.2 before 6.4.0.12; 6.5.0 before 6.6.4; 6.7.0 before 6.7.0.2 · source: NVD
Affected product
AS
Adaptive Security Appliance Software
Cisco
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-1501
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-1501
Vendor Advisory
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asa-ftd-sipdos-GGwmMerC
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