Security readout for executives and security teams
Plain-English summary
CVE-2020-3351 can let an unauthenticated remote attacker crash services in Cisco SD-WAN Solution Software by sending malformed UDP-encapsulated peering messages. The business risk is availability: affected SD-WAN devices, and devices depending on them, may lose service. The source bundle does not specify affected versions or fixed releases.
Executive priority
Treat this as a high-priority availability risk for Cisco SD-WAN environments. It does not indicate data theft, but service interruption could affect dependent branches, applications, and network resilience. Prioritize internet- or untrusted-network-reachable SD-WAN devices first.
Technical view
Cisco describes improper validation of fields in SD-WAN peering messages encapsulated in UDP packets. The CVSS 3.0 score is 8.6 with network attack vector, low complexity, no privileges, no user interaction, changed scope, and high availability impact only. CWE-399 is listed. Product coverage is Cisco SD-WAN Solution with versions marked n/a.
Likely exposure
Exposure is most likely in organizations operating Cisco SD-WAN Solution devices that can receive SD-WAN peering UDP traffic from reachable networks. The bundle does not identify specific vulnerable versions, so inventory must be compared with Cisco’s advisory and local deployment topology.
Exploitation context
The source supports unauthenticated remote denial of service through crafted UDP messages. It does not support confidentiality or integrity compromise. CISA KEV status is false in the bundle, and no cited source states active exploitation.
Researcher notes
Evidence is limited to the CVE record and Cisco advisory reference. The public bundle names the flaw class, protocol context, impact, and CVSS vector, but not affected releases, fixed versions, workarounds, or exploit-in-the-wild evidence.
Mitigation direction
- Review Cisco’s advisory for affected and fixed release guidance.
- Prioritize vendor-supported upgrades where Cisco identifies vulnerable software.
- Restrict SD-WAN peering UDP exposure to trusted network paths where feasible.
- Monitor SD-WAN devices for unexpected service failures or availability drops.
- Prepare operational rollback or failover plans for critical SD-WAN sites.
Validation and detection
- Inventory Cisco SD-WAN Solution devices and software versions.
- Compare deployed versions against Cisco advisory guidance.
- Map which devices receive SD-WAN peering UDP traffic from untrusted paths.
- Review logs and monitoring for unexplained SD-WAN service failures.
- Confirm compensating network controls do not break legitimate SD-WAN peering.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-399: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2020-3351 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- High
- CVSS
- 8.6 (3.0)
- Known Exploited
- No
- Published
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H3.94Primary CVE scoreVulnerability scoring details
Base CVSS 3.0 score
8.6HighVector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Source materials
- CVE List V5 sourceCVE List V5
- 20200715 Cisco SD-WAN Solution Software Denial of Service VulnerabilityCVE reference · vendor-advisory, x_refsource_CISCO
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Resource Management Errors
Resource Management Errors represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.