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7.4 High

CVE-2025-20340 A vulnerability in the Address Resolution Protocol (ARP) implementation of Cisco IOS XR Software could allow an…

Description

A vulnerability in the Address Resolution Protocol (ARP) implementation of Cisco IOS XR Software could allow an unauthenticated, adjacent attacker to trigger a broadcast storm, leading to a denial of service (DoS) condition on an affected device.  This vulnerability is due to how Cisco IOS XR Software processes a high, sustained rate of ARP traffic hitting the management interface. Under certain conditions, an attacker could exploit this vulnerability by sending an excessive amount of traffic to the management interface of an affected device, overwhelming its ARP processing capabilities. A successful exploit could result in degraded device performance, loss of management connectivity, and complete unresponsiveness of the system, leading to a DoS condition.

Affected products and versions

Product Affected versions Fixed in
Cisco IOS XR Software 25.1.1 No fix stated
Cisco IOS XR Software 24.4 24.4.1 → 24.4.30 No fix stated
Cisco IOS XR Software 24.3 24.3.1 → 24.3.30 No fix stated
Cisco IOS XR Software 24.2 24.2.1 → 24.2.20 No fix stated
Cisco IOS XR Software 24.1 24.1.1 → 24.1.2 No fix stated
Cisco IOS XR Software 7.11 7.11.1 → 7.11.21 No fix stated
Cisco IOS XR Software 7.10 7.10.1 → 7.10.2 No fix stated
Cisco IOS XR Software 7.9 7.9.1 → 7.9.21 No fix stated
Cisco IOS XR Software 7.8 7.8.1 → 7.8.23 No fix stated
Show the 13 other branches
Product Affected versions Fixed in
Cisco IOS XR Software 7.7 7.7.1 → 7.7.21 No fix stated
Cisco IOS XR Software 7.6 7.6.1 → 7.6.15 No fix stated
Cisco IOS XR Software 7.5 7.5.1 → 7.5.52 No fix stated
Cisco IOS XR Software 7.4 7.4.1 → 7.4.16 No fix stated
Cisco IOS XR Software 7.3 7.3.1 → 7.3.27 No fix stated
Cisco IOS XR Software 7.2 7.2.0 → 7.2.12 No fix stated
Cisco IOS XR Software 7.1 7.1.1 → 7.1.25 No fix stated
Cisco IOS XR Software 7.0 7.0.0 → 7.0.90 No fix stated
Cisco IOS XR Software 6.9 6.9.1 → 6.9.2 No fix stated
Cisco IOS XR Software 6.8 6.8.1 → 6.8.2 No fix stated
Cisco IOS XR Software 6.7 6.7.1 → 6.7.35 No fix stated
Cisco IOS XR Software 6.6 6.6.1 → 6.6.25 No fix stated
Cisco IOS XR Software 6.5 6.5.1 → 6.5.352 No fix stated

References

Timeline

  1. Published
  2. Last modified

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