CVE-2026-20277
Cisco IOS XR Software Security Hardening Release: September 2026
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-2026-20277 are related to protection mechanism failure issues that are grouped under the Common Weakness Enumeration (CWE) CWE-693.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- Low
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
Cisco IOS XR Software Security Hardening Release: September 2026
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-2026-20277 are related to protection mechanism failure issues that are grouped under the Common Weakness Enumeration (CWE) CWE-693.
- Record
CVE-2026-20277- CVSS 3.1
- 8.2 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H - Weakness
- CWE-693
- Updated
- 2026-11-02
EUVDEUVD-2026-70202
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-2026-20277 are related to protection mechanism failure issues that are grouped under the Common Weakness Enumeration (CWE) CWE-693.
- Record
EUVD-2026-70202- CVSS 3.1
- 8.2 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-6p8v-vwv7-4vg4
As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco IOS XR...
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-2026-20277 are related to protection mechanism failure issues that are grouped under the Common Weakness Enumeration (CWE) CWE-693.
- Record
GHSA-6p8v-vwv7-4vg4- CVSS 3.1
- 8.2 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H - Weakness
- CWE-693
- Updated
- 2026-11-02
NVD
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-2026-20277 are related to protection mechanism failure issues that are grouped under the Common Weakness Enumeration (CWE) CWE-693.
- Record
CVE-2026-20277- CVSS 3.1
- 8.2 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H - Weakness
- CWE-693
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-20277 is a high vulnerability (CVSS 8.2) in Cisco Ios Xr Software, published September 2, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.41%, the 35th percentile. No source names a fixed version.