CVE-2019-1951
mediumpriority · track · 24EPSS 0.015 · 73 %ileEURUUSEPSS · scored 2026-10-27
A vulnerability in the packet filtering features of Cisco SD-WAN Solution could allow an unauthenticated, remote attacker to bypass L3 and L4 traffic filters. The vulnerability is due to improper traffic filtering conditions on an affected device. An attacker could exploit this vulnerability by crafting a malicious TCP packet with specific characteristics and sending it to a target device. A successful exploit could allow the attacker to bypass the L3 and L4 traffic filters and inject an arbitrary packet in the network.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- FixedCisco SD-WAN Solutioncisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (4)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- cisco-sa-20190807-sd-wan-bypassCisco SD-WAN Solution Packet Filtering Bypass Vulnerability2019-08-07csaf · cisco_csafUS
A vulnerability in the packet filtering features of Cisco SD-WAN Solution could allow an unauthenticated, remote attacker to bypass L3 and L4 traffic filters. The vulnerability is due to improper traffic filtering conditions on an affected device. An attacker could exploit this vulnerability by crafting a malicious TCP packet with specific characteristics and sending it to a target device. A successful exploit could allow the attacker to bypass the L3 and L4 traffic filters and inject an arbitrary packet in the network. There are no workarounds that address this vulnerability. This advisory is available at the following link: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190807-sd-wan-bypass ["https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190807-sd-wan-bypass"]
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (8)
External citations — patches, advisories, analysis.
- https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvn67202Patchcnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2019-1951cnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190807-sd-wan-bypasscnnvd
- https://vigilance.fr/vulnerability/Cisco-SD-WAN-Solution-privilege-escalation-via-L3-L4-Traffic-Filter-Bypass-29981cnnvd
- https://www.auscert.org.au/bulletins/ESB-2019.2991.2/cnnvd
- https://www.auscert.org.au/bulletins/ESB-2019.2991/cnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190807-sd-wan-bypassenisa_euvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190807-sd-wan-bypassVendor Advisorynvd
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