CVE-2018-0277
mediumpriority · track · 35EPSS 0.023 · 83 %ileEUUSEPSS · scored 2026-10-27
A vulnerability in the Extensible Authentication Protocol-Transport Layer Security (EAP-TLS) certificate validation during EAP authentication for the Cisco Identity Services Engine (ISE) could allow an unauthenticated, remote attacker to cause the ISE application server to restart unexpectedly, causing a denial of service (DoS) condition on an affected system. The vulnerability is due to incomplete input validation of the client EAP-TLS certificate. An attacker could exploit this vulnerability by initiating EAP authentication over TLS to the ISE with a crafted EAP-TLS certificate. A successful exploit could allow the attacker to restart the ISE application server, resulting in a DoS condition on the affected system. The ISE application could continue to restart while the client attempts to establish the EAP authentication connection. If an attacker attempted to import the same EAP-TLS certificate to the ISE trust store, it could trigger a DoS condition on the affected system. This exploit vector would require the attacker to have valid administrator credentials. The vulnerability affects Cisco ISE, Cisco ISE Express, and Cisco ISE Virtual Appliance. Cisco Bug IDs: CSCve31857.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- FixedCisco Identity Services Engine Softwarecisco_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 · 5–8.6
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (6)
Products and version ranges known to be affected.
- cisco identity services engine= 2.0(0.306)nvdUScpe:2.3:a:cisco:identity_services_engine:*:*:*:*:*:*:*:*
- cisco identity services engine= 2.0(1.130)nvdUScpe:2.3:a:cisco:identity_services_engine:*:*:*:*:*:*:*:*
- cisco identity services engine= 2.1(0.474)nvdUScpe:2.3:a:cisco:identity_services_engine:*:*:*:*:*:*:*:*
- cisco identity services engine= 2.2(0.470)nvdUScpe:2.3:a:cisco:identity_services_engine:*:*:*:*:*:*:*:*
advisories (1)
Vendor and ecosystem advisories describing this.
- cisco-sa-20180516-iseeapCisco Identity Services Engine EAP TLS Certificate Denial of Service Vulnerability2018-05-16csaf · cisco_csafUS
A vulnerability in the Extensible Authentication Protocol-Transport Layer Security (EAP-TLS) certificate validation during EAP authentication for the Cisco Identity Services Engine (ISE) could allow an unauthenticated, remote attacker to cause the ISE application server to restart unexpectedly, causing a denial of service (DoS) condition on an affected system. The vulnerability is due to incomplete input validation of the client EAP-TLS certificate. An attacker could exploit this vulnerability by initiating EAP authentication over TLS to the ISE with a crafted EAP-TLS certificate. A successful exploit could allow the attacker to restart the ISE application server, resulting in a DoS condition on the affected system. The ISE application could continue to restart while the client attempts to establish the EAP authentication connection. If an attacker attempted to import the same EAP-TLS certificate to the ISE trust store, it could trigger a DoS condition on the affected system. This exploit vector would require the attacker to have valid administrator credentials. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. This advisory is available at the following link: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180516-iseeap ["https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180516-iseeap"]
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (9)
External citations — patches, advisories, analysis.
- http://www.securitytracker.com/id/1040922cnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180516-iseeapcnnvd
- https://www.securityfocus.com/bid/104212cnnvd
- http://www.securityfocus.com/bid/104212enisa_euvd
- http://www.securitytracker.com/id/1040922enisa_euvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180516-iseeapenisa_euvd
- http://www.securityfocus.com/bid/104212Third Party AdvisoryVDB Entrynvd
- http://www.securitytracker.com/id/1040922Third Party AdvisoryVDB Entrynvd
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