cbcvebase.
CVE-2025-20221
published 2025-05-07

CVE-2025-20221: A vulnerability in the packet filtering features of Cisco IOS XE SD-WAN Software could allow an unauthenticated, remote attacker to bypass Layer 3 and Layer 4…

PriorityP263critical9.1CVSS 3.1
AVNACLPRNUINSUCHIHAN
EPSS
0.42%
34.0th percentile
A vulnerability in the packet filtering features of Cisco IOS XE SD-WAN Software could allow an unauthenticated, remote attacker to bypass Layer 3 and Layer 4 traffic filters. This vulnerability is due to improper traffic filtering conditions on an affected device. An attacker could exploit this vulnerability by sending a crafted packet to the affected device. A successful exploit could allow the attacker to bypass the Layer 3 and Layer 4 traffic filters and inject a crafted packet into the network.

Affected

179 ranges· showing 25
VendorProductVersion rangeFixed in
ciscocisco_ios_xe_software
ciscocisco_ios_xe_software
ciscocisco_ios_xe_software
ciscocisco_ios_xe_software
ciscocisco_ios_xe_software
ciscocisco_ios_xe_software
ciscocisco_ios_xe_software
ciscocisco_ios_xe_software
ciscocisco_ios_xe_software
ciscocisco_ios_xe_software
ciscocisco_ios_xe_software
ciscocisco_ios_xe_software
ciscocisco_ios_xe_software
ciscocisco_ios_xe_software
ciscocisco_ios_xe_software
ciscocisco_ios_xe_software
ciscocisco_ios_xe_software
ciscocisco_ios_xe_software
ciscocisco_ios_xe_software
ciscocisco_ios_xe_software
ciscocisco_ios_xe_software
ciscocisco_ios_xe_software
ciscocisco_ios_xe_software
ciscocisco_ios_xe_software
ciscocisco_ios_xe_software

Detection & IOCsextracted from sources · hover to see the quote

  • Detect crafted packets attempting to bypass Layer 3 and Layer 4 traffic filters on Cisco IOS XE SD-WAN devices by monitoring for unexpected traffic that should have been filtered by configured ACLs or policy rules.
  • Reference Cisco Bug ID CSCwn25087 when querying vendor threat intelligence feeds or internal ticketing for affected device identification.
  • ·The vulnerability is due to improper traffic filtering conditions on the affected device; review and validate all Layer 3/Layer 4 packet filter configurations on Cisco IOS XE SD-WAN deployments to ensure filters are enforced as expected.
  • ·Workarounds exist for this vulnerability in addition to software updates; consult the Cisco Security Advisory for specific workaround guidance applicable to your deployment.

CVSS provenance

nvdv3.19.1CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
vendor_cisco5.3MEDIUM
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