Vulnerability · Published Aug 17, 2020 · Assigned by cisco

CVE-2020-3449Cisco IOS XR Software Additional Paths Denial of Service Vulnerability

Medium 4.3

In plain English

A medium-severity security flaw in Cisco IOS XR Software from Cisco. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.1% (higher than 65% of all known vulnerabilities).

Severity (CVSS 3.1)4.3Medium

Exploit odds (30 days)1.1%top 35.4% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

A vulnerability in the Border Gateway Protocol (BGP) additional paths feature of Cisco IOS XR Software could allow an unauthenticated, remote attacker to prevent authorized users from monitoring the BGP status and cause the BGP process to stop processing new updates, resulting in a denial of service (DOS) condition. The vulnerability is due to an incorrect calculation of lexicographical order when displaying additional path information within Cisco IOS XR Software, which causes an infinite loop. An attacker could exploit this vulnerability by sending a specific BGP update from a BGP neighbor peer session of an affected device; an authorized user must then issue a show bgp command for the vulnerability to be exploited. A successful exploit could allow the attacker to prevent authorized users from properly monitoring the BGP status and prevent BGP from processing new updates, resulting in outdated information in the routing and forwarding tables.

Affected products (as reported)

Vendor	Product	Versions
Cisco	Cisco IOS XR Software	n/a

Weakness: CWE-754 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L

References

20200805 Cisco IOS XR Software Additional Paths Denial of Service Vulnerability vendor-advisory, x_refsource_CISCO