Affects Cisco Identity Services Engine, a widely deployed enterprise network access control product; DoS can cause authentication outages and network disruption across organizations.
CVE-2026-20352
Crafted RADIUS requests can cause DoS on Cisco ISE nodes
Is CVE-2026-20352 being exploited?
Not confirmed. CVE-2026-20352 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.57% probability of exploitation in the next 30 days.
How severe is CVE-2026-20352?
CVE-2026-20352 is rated High with a CVSS score of 8.6. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-20352?
Not known from our data. No patch reference has been recorded for CVE-2026-20352, which is not the same as no patch existing — a fix may have shipped without a tagged reference, or after this record was written. The vendor advisory is the only authority on whether a fix exists, and mitigations may be available regardless.
What does CVE-2026-20352 affect?
CVE-2026-20352 affects Cisco Identity Services Engine (ISE) - RADIUS feature, ISE nodes (single-node deployments at high risk). Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-20352?
Restrict RADIUS access to trusted sources, apply Cisco mitigations, patch when vendor update is released.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Unauthenticated remote attacker can send crafted RADIUS requests to crash an ISE node, causing authentication outages and loss of network access for endpoints.
Immediate action required
- affected3.2.0
- affected3.2.0 p1
- affected3.2.0 p2
- affected3.3.0
- affected3.2.0 p3
- affected3.2.0 p4
- affected3.2.0 p5
- affected3.2.0 p6
- affected3.3 Patch 2
- affected3.3 Patch 1
- affected3.3 Patch 3
- affected3.4.0
- affected3.2.0 p7
- affected3.3 Patch 4
- affected3.4 Patch 1
- affected3.3 Patch 5
- affected3.3 Patch 6
- affected3.4 Patch 2
- affected3.3 Patch 7
- affected3.4 Patch 3
- affected3.5.0
- affected3.4 Patch 4
- affected3.3 Patch 8
- affected3.2 Patch 8
- affected3.5 Patch 1
- affected3.3 Patch 9
- affected3.2 Patch 9
- affected3.4 Patch 5
- affected3.5 Patch 3
- affected3.5 Patch 2
- affected3.3 Patch 10
- affected3.3 Patch 11
- affected3.4 Patch 6
- affected3.2 Patch 10
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.
cisa ssvc
- exploitation
- none
- automatable
- yes
- technical impact
- partial
Assessed by CISA 17 Sept 2026 (SSVC 2.0.3).
timeline
- 16 Sept 2026Published
- 17 Sept 2026CISA SSVC assessment: exploitation none · 1 day later
- 17 Sept 2026CVE record last updated · same day later
- 19 Sept 2026Analysed by vulneraibility.com · 2 days later
- Linksec.cloudapps.cisco.com /security/center/content/CiscoSecurityAdvisory/cisco-sa-ise-RADIUS-dos-wR3hYPMw
sources
- CVE List (CVE.org): description, affected versions, references; CVE Terms of Use
- NVD: CVSS and CPE data
- CISA Vulnrichment (ADP): SSVC decision points
- FIRST EPSS: exploit probability and percentile
- Summary, impact and triage tags: written by our AI analysis pipeline from the sources above. Check them against the sources.