CVE-2018-15397
highpriority · track · 27EPSS 0.012 · 68 %ileEURUUSEPSS · scored 2026-10-27
A vulnerability in the implementation of Traffic Flow Confidentiality (TFC) over IPsec functionality in Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause an affected device to restart unexpectedly, resulting in a denial of service (DoS) condition. The vulnerability is due to an error that may occur if the affected software renegotiates the encryption key for an IPsec tunnel when certain TFC traffic is in flight. An attacker could exploit this vulnerability by sending a malicious stream of TFC traffic through an established IPsec tunnel on an affected device. A successful exploit could allow the attacker to cause a daemon process on the affected device to crash, which could cause the device to crash and result in a DoS condition.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- Fixed6.2.2cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed9.6.4cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed9.8.2cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed9.9.1cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.2–7.1
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (15)
Products and version ranges known to be affected.
- cisco adaptive security appliance software= 9.6.4nvdUScpe:2.3:o:cisco:adaptive_security_appliance_software:*:*:*:*:*:*:*:*
- cisco adaptive security appliance software= 9.8.2nvdUScpe:2.3:o:cisco:adaptive_security_appliance_software:*:*:*:*:*:*:*:*
- cisco adaptive security appliance software= 9.9.1nvdUScpe:2.3:o:cisco:adaptive_security_appliance_software:*:*:*:*:*:*:*:*
- cisco adaptive security appliance software= 9.9.1(1)nvdUScpe:2.3:o:cisco:adaptive_security_appliance_software:*:*:*:*:*:*:*:*
- cisco secure firewall management center= 6.2.2nvdUScpe:2.3:a:cisco:secure_firewall_management_center:*:*:*:*:*:*:*:*
advisories (1)
Vendor and ecosystem advisories describing this.
- cisco-sa-20181003-asa-ipsec-dosCisco Adaptive Security Appliance IPsec VPN Denial of Service Vulnerability2018-10-03csaf · cisco_csafUS
A vulnerability in the implementation of Traffic Flow Confidentiality (TFC) over IPsec functionality in Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause an affected device to restart unexpectedly, resulting in a denial of service (DoS) condition. The vulnerability is due to an error that may occur if the affected software renegotiates the encryption key for an IPsec tunnel when certain TFC traffic is in flight. An attacker could exploit this vulnerability by sending a malicious stream of TFC traffic through an established IPsec tunnel on an affected device. A successful exploit could allow the attacker to cause a daemon process on the affected device to crash, which could cause the device to crash and result in a DoS condition. There are no workarounds that address this vulnerability.
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (6)
External citations — patches, advisories, analysis.
- http://www.securitytracker.com/id/1041786cnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20181003-asa-ipsec-doscnnvd
- http://www.securitytracker.com/id/1041786enisa_euvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20181003-asa-ipsec-dosenisa_euvd
- http://www.securitytracker.com/id/1041786Third Party AdvisoryVDB Entrynvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20181003-asa-ipsec-dosVendor Advisorynvd
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