Actively exploited in the wild
Cisco IOS XR Border Gateway Protocol (BGP) Denial-of-Service Vulnerability
Cisco - IOS XR · Listed in the CISA KEV since 2022-03-25. This indicates confirmed attacks in production environments.
Required action: Apply updates per vendor instructions.
CVE-2009-2055
MediumCVSS 5.9KEVSummary
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.
Risk Assessment
A remote attacker can reset BGP sessions, causing routing disruptions and service unavailability for users and systems relying on network connectivity.
Recommendation
Upgrade Cisco IOS XR to a fixed version and implement BGP message filtering and validation from peers to reduce the risk of exploitation.
Other vulnerabilities in Cisco IOS XR
See all- CVE-2016-6428High
Cisco IOS XR version 6.1.1 allows local users to execute arbitrary OS commands as root by leveraging admin privileges.
- CVE-2016-1456High
The CLI in Cisco IOS XR versions 6.x through 6.0.1 allows local users to execute arbitrary OS commands in a privileged context by leveraging unspecified container access.
- CVE-2016-1407High
Cisco IOS XR versions up to 5.3.2 mishandle Local Packet Transport Services (LPTS) flow-based entries, allowing remote attackers to cause a denial of service (session drop) by making many connection attempts to open TCP ports.
- CVE-2015-6432High
Cisco IOS XR versions 4.2.0, 4.3.0, 5.0.0, 5.1.0, 5.2.0, 5.2.2, 5.2.4, 5.3.0, and 5.3.2 do not properly restrict the number of Path Computation Elements (PCEs) for OSPF LSA opaque area updates, allowing remote attackers to cause a denial of service (device reload) via a crafted update.
- CVE-2015-0618High
Cisco IOS XR versions 5.0.1 and 5.2.1 on Network Convergence System 6000 devices and 5.1.3 and 5.1.4 on Carrier Routing System X devices allow remote attackers to cause a denial of service (line-card reload) via malformed IPv6 packets with extension headers.
- CVE-2014-3353High
Cisco IOS XR 4.3(.2) and earlier, used in Cisco Carrier Routing System (CRS), allows remote attackers to cause a denial of service by sending a malformed IPv6 packet.
- CVE-2026-20279Critical
A vulnerability in Cisco IOS XR Software relates to improper access control issues (CWE-284). It was discovered during an internal security review and addressed in software hardening releases.
- CVE-2026-20274Critical
A vulnerability in Cisco IOS XR Software relates to improper resource control issues (CWE-664). It was discovered during an internal security review and addressed in software hardening releases.
Original NVD description (English source)
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.