Cisco IOS XR 3.4.0 through 3.8.1 allows remote attackers to cause a denial of service (session reset) via a BGP UPDATE message with an invalid attribute, as demonstrated in the wild on 17 August 2009.
Cisco IOS XR 3.4.0 through 3.8.1 allows remote attackers to cause a denial of service (session reset) via a BGP UPDATE message with an invalid attribute, as demonstrated in the wild on 17 August 2009.
Why this VPI (explainable, experimental)
VPI breakdown
| Impact | 59.00 |
| Exploitation signal(KEV listed) | ×1.50 |
| VPI | 88.50 |
VPI formula vpi-v1
Required Action
Apply updates per vendor instructions.
| Source | CVSS Version | Base Score | Severity | Vector String | Assessment Date |
|---|---|---|---|---|---|
| NVDNIST | 3.1 | 5.9 | MEDIUM | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H | 04/20/2026 |
| NVDNIST | 2.0 | 4.3 |
| AV:N/AC:M/Au:N/C:N/I:N/A:P |
| 04/20/2026 |