Security readout for executives and security teams
Plain-English summary
CVE-2021-1513 can let an unauthenticated remote attacker crash and reload affected Cisco SD-WAN devices, causing a denial of service. The business risk is service disruption to WAN connectivity, not data theft or tampering based on the provided sources.
Executive priority
Treat as high priority for environments dependent on Cisco SD-WAN availability, especially exposed edge deployments. The main risk is outage or degraded WAN service, so remediation should align with business-critical routing and branch connectivity impact.
Technical view
The vulnerability is in Cisco SD-WAN Software's vDaemon process. Insufficient handling of malformed packets can allow crafted traffic to trigger a device reload. CVSS 3.1 is 7.5 with network attack vector, low complexity, no privileges, no user interaction, and high availability impact only.
Likely exposure
Exposure is limited to organizations running Cisco SD-WAN Solution devices with affected SD-WAN Software. The source bundle does not specify affected release numbers, so teams must map inventory against Cisco's advisory before determining scope.
Exploitation context
The bundle does not show CISA KEV listing or any cited evidence of active exploitation. Exploitation requires network reachability to an affected device and crafted malformed traffic. Confirmed impact is device reload and denial of service.
Researcher notes
Evidence supports a remote unauthenticated DoS caused by malformed packet handling in vDaemon. The supplied data does not include affected version ranges, fixed releases, ports, packet details, or exploit-in-the-wild evidence. Avoid assuming broader impact beyond availability.
Mitigation direction
- Review Cisco's advisory for affected releases and fixed software guidance.
- Prioritize remediation for internet-facing or untrusted-reachable SD-WAN devices.
- Restrict untrusted network access to affected SD-WAN devices where feasible.
- Monitor for unexpected device reloads and vDaemon crash indicators.
- Ensure operational runbooks cover SD-WAN device reload disruption.
Validation and detection
- Inventory Cisco SD-WAN Solution devices and installed software versions.
- Compare versions against Cisco's advisory before declaring systems affected or clear.
- Check logs and monitoring for unexplained reloads or vDaemon failures.
- Confirm network paths that can reach SD-WAN device services.
- Verify remediation status after applying vendor-directed updates or mitigations.
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
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CWE-20: Exact CWE lookup
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Open ATT&CK lookupCVE-2021-1513 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
- 7.5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/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:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H3.93.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
7.5HighVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Source materials
- CVE List V5 sourceCVE List V5
- 20210505 Cisco SD-WAN Software vDaemon 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.
Improper Input Validation
Improper Input Validation represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.