Vulnerability in Cisco (CVE-2026-20177)
Summary
Vulnerability in Cisco (CVE-2026-20177). Risk of unauthorized operations or information disclosure.
Original description
The description as published by the source.
A vulnerability in the handling of management plane packets by Cisco Industrial Ethernet (IE) 1000 Series Switches could allow an unauthenticated, remote attacker to cause the device manager, SSH, or API to become inaccessible.This vulnerability is due to insufficient protection against management plane flooding attacks. An attacker could exploit this vulnerability by sending a high rate of ICMP, SSH, or HTTP traffic to an affected device. A successful exploit could allow the attacker to cause the CPU of the device to increase, resulting in a denial of service (DoS) condition on the device manager web GUI, SSH, or API. Data traffic through the device is not affected.
Source: Cisco Security Advisories NVD GitHub Advisory
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-2026-20177 has been found in Cisco.
Risk of unauthorized operations or information disclosure. CVSS score: 5.3/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Cisco CVE-2026-20177" on the vendor's site.
CVE-2026-20177 (Cisco) — CWE-770 / CVSS v3 5.3
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-770) exists in Cisco.
Check the vendor advisory for the affected versions of Cisco.
Severity: Medium (CVSS 5.3/10). 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 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
- web psirt@cisco.com
- web nvd.nist.gov
- web github.com