Vulnerability in Cisco Crosswork Network Controller (CVE-2026-20188)
Summary
Vulnerability in Cisco Crosswork Network Controller (CVE-2026-20188). Risk of unauthorized operations or information disclosure.
Original description
The description as published by the source.
A vulnerability in the connection-handling mechanism of Cisco Crosswork Network Controller (CNC) and Cisco Network Services Orchestrator (NSO) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected system. This vulnerability is due to an inadequate implementation of rate-limiting on incoming network connections. An attacker could exploit this vulnerability by sending a large number of connection requests to an affected system. A successful exploit could allow the attacker to exhaust available connection resources, causing Cisco CNC and Cisco NSO to become unresponsive and resulting in a DoS condition for legitimate users and dependent services. A manual reboot of the system is required to recover from this condition. 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-nso-dos-7Egqyc Security Impact Rating: High CVE: CVE-2026-20188
Source: Cisco Security Advisories NVD
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-20188 has been found in Cisco Crosswork Network Controller.
Risk of unauthorized operations or information disclosure.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Cisco Crosswork Network Controller CVE-2026-20188" on the vendor's site.
CVE-2026-20188 (Cisco Crosswork Network Controller) — CWE-400
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-400) exists in Cisco Crosswork Network Controller.
Check the vendor advisory for the affected versions of Cisco Crosswork Network Controller.
Severity: ?. Risk of unauthorized operations or information disclosure.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで Cisco Crosswork Network Controller を使っているサービスとバージョンを洗い出す。
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2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
References
- CISCO sec.cloudapps.cisco.com
- CISCO sec.cloudapps.cisco.com
- web psirt@cisco.com