PT-2009-4509 · Cisco · Cisco Ios Xr

Published 2009-08-18 · Updated 2009-08-21 · CVE-2009-2056

Positive Technologies (AI Summary)

CVSS v2.0

3.3

Low

Base vector

AV:N/AC:L/Au:M/C:N/I:N/A:P

Name of the Vulnerable Software and Affected Versions Cisco IOS XR versions 3.8.1 and earlier

Description The issue allows remote authenticated users to cause a denial of service via vectors involving a BGP UPDATE message with many AS numbers prepended to the AS path. Specifically, the Cisco IOS XR Software contains multiple vulnerabilities in the Border Gateway Protocol (BGP) feature. These include the reset of a BGP peering session when receiving a specific invalid BGP update, the crash of the BGP process when sending a long length BGP update message, and the crash of the BGP process when constructing a BGP update with a large number of AS prepends.

Recommendations For Cisco IOS XR versions 3.8.1 and earlier, consider applying the free software maintenance upgrade (SMU) released by Cisco to address these vulnerabilities. As a temporary workaround, restrict the number of AS numbers that can be prepended to the AS path to prevent the BGP process from crashing. Additionally, avoid sending long length BGP update messages to minimize the risk of exploitation.

Fix

DoS

Weakness Enumeration

CWE-264

Related Identifiers

CVE-2009-2056

Affected Products

Cisco Ios Xr

References · 4

• http://cisco.com/en/US/products/products_security_advisory09186a0080af150f.shtml · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2009-2056 · Security Note
• https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20090818-bgp · Vendor Advisory
• http://securitytracker.com/id?1022756 · Note