CVE-2009-2055: Cisco IOS XR Border Gateway Protocol (BGP) Denial-of-Service Vulnerability

Severity: medium (CVSS 4.3 v2.0)
Exploited in the wild: yes — in CISA KEV since 2022-03-25
EPSS: 3.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2009-08-19 · updated 2026-06-16
Weakness: CWE-20

Description

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.

Affected products

Cisco IOS XR Software: 3.4, 3.4.0, 3.4.1, 3.4.2, 3.4.3, 3.5 (+13)

References

http://mailman.nanog.org/pipermail/nanog/2009-August/012719.html
http://securitytracker.com/id?1022739
http://www.cisco.com/en/US/products/products_security_advisory09186a0080af150f.shtml
http://mailman.nanog.org/pipermail/nanog/2009-August/012719.html
http://securitytracker.com/id?1022739
http://www.cisco.com/en/US/products/products_security_advisory09186a0080af150f.shtml
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2009-2055

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