Cisco Firepower Threat Defense vulnerabilities: known CVEs & security history
Cisco · Network security · 11 tracked CVEs · 2 actively exploited · updated September 2026 · what is a CVE? →
This is the full list of known vulnerabilities (CVEs) across all Cisco Firepower Threat Defense release lines — 11 in total, with 2 actively exploited in the wild. A CVE here doesn't mean your version is affected — check Cisco Firepower Threat Defense's current status and the safe version to run.
Known Cisco Firepower Threat Defense CVEs
Actively-exploited and most-severe first. Open any CVE for full details.
| CVE | Severity | CVSS | EPSS | Year |
|---|---|---|---|---|
| CVE-2018-0296⚡ exploited | high | 7.5 | 100% | 2018 |
| CVE-2023-20269⚡ exploited | medium | 5 | 22% | 2023 |
| CVE-2018-15383 | high | 7.5 | 2% | 2018 |
| CVE-2017-6632 | high | 7.5 | 2% | 2017 |
| CVE-2020-3583 | medium | 6.1 | 1% | 2020 |
| CVE-2020-3582 | medium | 6.1 | 1% | 2020 |
| CVE-2020-3581 | medium | 6.1 | 1% | 2020 |
| CVE-2026-20017 | medium | 6 | 0% | 2026 |
| CVE-2022-20922 | medium | 5.8 | 1% | 2022 |
| CVE-2020-3585 | medium | 5.3 | 1% | 2020 |
| CVE-2020-3578 | medium | 5.3 | 1% | 2020 |
Is my Cisco Firepower Threat Defense version affected?
The list above spans every release. To know whether your version is affected — and the minimum safe version to upgrade to — check it directly.
Check your Cisco Firepower Threat Defense version → · Monitor Cisco Firepower Threat Defense for new CVEs →
Cisco Firepower Threat Defense vulnerabilities — frequently asked
How many known vulnerabilities does Cisco Firepower Threat Defense have?
IsItPatched tracks 11 CVEs for Cisco Firepower Threat Defense, 2 of which are actively exploited (CISA KEV). 0 are critical-severity and 3 high-severity. These span every release line — what matters is whether the version you run is affected.
Does Cisco Firepower Threat Defense have any actively-exploited vulnerabilities?
Yes — 2 Cisco Firepower Threat Defense CVEs are in CISA's Known Exploited Vulnerabilities catalog, meaning they are confirmed exploited in the wild (1 linked to ransomware). Patch these as a priority.
What is the most severe Cisco Firepower Threat Defense vulnerability?
Among tracked issues, CVE-2018-0296 (HIGH, CVSS 7.5), which is actively exploited, ranks highest — a Improper input validation weakness.
Is Cisco Firepower Threat Defense safe to use?
It depends on the version. The latest supported Cisco Firepower Threat Defense release clears the known issues; older versions may still be affected. Check the exact version you run for a verdict.
CVE data aggregated from NVD, CISA KEV and EPSS (FIRST.org). Related: Cisco Firepower Threat Defense security status · Cisco Firepower Threat Defense end-of-life · actively-exploited CVEs. Always verify against Cisco's advisories — see our disclaimer.