CVE-2026-20276
High
Description
As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco IOS XR Software engineering team has conducted a comprehensive internal security review. This review resulted in a software hardening releases that address multiple internally discovered vulnerabilities. The vulnerabilities tracked by CVE-2026-20276 are related to insufficient control flow management issues that are grouped under the Common Weakness Enumeration (CWE) CWE-691.
SeverityHigh
CVSS8.6
Exploit probability—
Product
Cisco Ios Xr
PublishedSep 2, 2026
First seenSep 2, 2026
Weakness typeCWE-691CWE-691
How to fix
Sources list no fixed version or patch link for this vulnerability.
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| cisco ios_xr | 6.5.25, 6.5.26, 6.5.28, 6.5.29, 6.5.31, 6.5.32, 6.5.33, 6.5.35, 6.5.90, 6.5.351, 6.5.352, 6.5.353, 6.7.1, 6.7.2, 6.7.3, 6.7.4, 6.7.35, 6.8.1, 6.8.2, 6.9.1, 6.9.2, 7.0.0, 7.0.1, 7.0.2, 7.0.11, 7.0.12, 7.0.14, 7.0.90, 7.1.1, 7.1.2, 7.1.3, 7.1.15, 7.1.25, 7.2.0, 7.2.1, 7.2.2, 7.2.12, 7.3.1, 7.3.2, 7.3.3, 7.3.4, 7.3.5, 7.3.6, 7.3.15, 7.3.16, 7.3.27, 7.4.1, 7.4.2, 7.4.15, 7.4.16, 7.5.1, 7.5.2, 7.5.3, 7.5.4, 7.5.5, 7.5.12, 7.5.52, 7.6.1, 7.6.2, 7.6.3, 7.6.15, 7.7.1, 7.7.2, 7.7.21, 7.8.1, 7.8.2, 7.8.12, 7.8.22, 7.8.23, 7.9.1, 7.9.2, 7.9.21, 7.10.1, 7.10.2, 7.11.1, 7.11.2, 7.11.21, 24.1.1, 24.1.2, 24.2.1, 24.2.2, 24.2.11, 24.2.20, 24.2.21, 24.3.1, 24.3.2, 24.3.20, 24.3.30, 24.4.1, 24.4.2, 24.4.10, 24.4.15, 24.4.30, 25.1.1, 25.1.2, 25.1.30, 25.2.1, 25.2.2, 25.2.15, 25.2.30, 25.3.1, 25.3.15, 25.4.1, 25.4.2, 25.4.30, 25.4.201, 26.1.1, 26.1.2, 26.2.1, 26.2.100, 26.2.101 | — |
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