CVE-2021-1594
highpriority · track · 32EPSS 0.014 · 72 %ileEURUUSEPSS · scored 2026-10-27
A vulnerability in the REST API of Cisco Identity Services Engine (ISE) could allow an unauthenticated, remote attacker to perform a command injection attack and elevate privileges to root. This vulnerability is due to insufficient input validation for specific API endpoints. An attacker in a man-in-the-middle position could exploit this vulnerability by intercepting and modifying specific internode communications from one ISE persona to another ISE persona. A successful exploit could allow the attacker to run arbitrary commands with root privileges on the underlying operating system. To exploit this vulnerability, the attacker would need to decrypt HTTPS traffic between two ISE personas that are located on separate nodes.
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
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (14)
Products and version ranges known to be affected.
- cisco identity services engine= 2.4(0.902)nvdUScpe:2.3:a:cisco:identity_services_engine:*:*:*:*:*:*:*:*
- cisco identity services engine2.4.0 → 2.6.0nvdUScpe:2.3:a:cisco:identity_services_engine:*:*:*:*:*:*:*:*
- cisco identity services engine= 2.6(0.156)nvdUScpe:2.3:a:cisco:identity_services_engine:*:*:*:*:*:*:*:*
- cisco identity services engine= 2.7(0.903)nvdUScpe:2.3:a:cisco:identity_services_engine:*:*:*:*:*:*:*:*
- cisco identity services engine= 3.0(0.458)nvdUScpe:2.3:a:cisco:identity_services_engine:*:*:*:*:*:*:*:*
- cisco identity services engine= 3.1(0.440)nvdUScpe:2.3:a:cisco:identity_services_engine:*:*:*:*:*:*:*:*
advisories (1)
Vendor and ecosystem advisories describing this.
- cisco-sa-ise-priv-esc-UwqPrBM3Cisco Identity Services Engine Privilege Escalation Vulnerability2021-10-06csaf · cisco_csafUS
A vulnerability in the REST API of Cisco Identity Services Engine (ISE) could allow an unauthenticated, remote attacker to perform a command injection attack and elevate privileges to root. This vulnerability is due to insufficient input validation for specific API endpoints. An attacker in a man-in-the-middle position could exploit this vulnerability by intercepting and modifying specific internode communications from one ISE persona to another ISE persona. A successful exploit could allow the attacker to run arbitrary commands with root privileges on the underlying operating system. To exploit this vulnerability, the attacker would need to decrypt HTTPS traffic between two ISE personas that are located on separate nodes. Cisco has released software updates that address this vulnerability. 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.
- https://nvd.nist.gov/vuln/detail/CVE-2021-1594cnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ise-priv-esc-UwqPrBM3cnnvd
- https://www.auscert.org.au/bulletins/ESB-2021.3316cnnvd
- https://www.cybersecurity-help.cz/vdb/SB2021100707cnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ise-priv-esc-UwqPrBM3enisa_euvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ise-priv-esc-UwqPrBM3Vendor Advisorynvd
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