Cisco IOS XE vulnerabilities: known CVEs & security history
Cisco · Network / Security · 15 tracked CVEs · 1 actively exploited · updated September 2026 · what is a CVE? →
This is the full list of known vulnerabilities (CVEs) across all Cisco IOS XE release lines — 15 in total, with 1 actively exploited in the wild. A CVE here doesn't mean your version is affected — check Cisco IOS XE's current status and the safe version to run.
Known Cisco IOS XE CVEs
Actively-exploited and most-severe first. Open any CVE for full details.
| CVE | Severity | CVSS | EPSS | Year |
|---|---|---|---|---|
| CVE-2023-44487⚡ exploited | high | 7.5 | 100% | 2023 |
| CVE-2026-20272 | critical | 9.8 | 0% | 2026 |
| CVE-2026-20267 | critical | 9 | 0% | 2026 |
| CVE-2025-20363 | critical | 9 | 8% | 2025 |
| CVE-2026-20273 | high | 8.6 | 0% | 2026 |
| CVE-2026-20271 | high | 8.6 | 0% | 2026 |
| CVE-2026-20270 | high | 8.6 | 0% | 2026 |
| CVE-2026-20269 | high | 8.6 | 0% | 2026 |
| CVE-2026-20268 | high | 8.6 | 0% | 2026 |
| CVE-2021-1223 | high | 7.5 | 2% | 2021 |
| CVE-2023-20081 | medium | 6.8 | 1% | 2023 |
| CVE-2023-20246 | medium | 5.8 | 1% | 2023 |
| CVE-2021-1495 | medium | 5.8 | 2% | 2021 |
| CVE-2021-1224 | medium | 5.8 | 2% | 2021 |
| CVE-2021-1236 | medium | 5.3 | 2% | 2021 |
Is my Cisco IOS XE 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 IOS XE version → · Monitor Cisco IOS XE for new CVEs →
Cisco IOS XE vulnerabilities — frequently asked
How many known vulnerabilities does Cisco IOS XE have?
IsItPatched tracks 15 CVEs for Cisco IOS XE, 1 of which is actively exploited (CISA KEV). 3 are critical-severity and 7 high-severity. These span every release line — what matters is whether the version you run is affected.
Does Cisco IOS XE have any actively-exploited vulnerabilities?
Yes — 1 Cisco IOS XE CVE is in CISA's Known Exploited Vulnerabilities catalog, meaning it is confirmed exploited in the wild. Patch it as a priority.
What is the most severe Cisco IOS XE vulnerability?
Among tracked issues, CVE-2023-44487 (HIGH, CVSS 7.5), which is actively exploited, ranks highest — a Uncontrolled resource consumption weakness.
Is Cisco IOS XE safe to use?
It depends on the version. The latest supported Cisco IOS XE 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 IOS XE security status · Cisco IOS XE end-of-life · actively-exploited CVEs. Always verify against Cisco's advisories — see our disclaimer.