Security readout for executives and security teams
Plain-English summary
CVE-2021-1614 is an information disclosure issue in Cisco SD-WAN Software MPLS packet handling. A remote unauthenticated attacker could cause affected devices to expose sensitive information from MPLS buffer memory. The known impact is confidentiality only, with no cited integrity or availability impact.
Executive priority
Treat this as a moderate confidentiality risk. It should be scheduled into normal network security remediation, with higher priority for SD-WAN environments connected to less trusted MPLS or partner networks.
Technical view
The issue is caused by insufficient handling of malformed MPLS packets in Cisco SD-WAN Software. The CVSS 3.1 score is 5.3 with network attack vector, low complexity, no privileges, and low confidentiality impact. The source bundle maps it to CWE-126, consistent with out-of-bounds read behavior.
Likely exposure
Exposure is most relevant for organizations running Cisco SD-WAN Software or Cisco SD-WAN vManage Software where affected devices process MPLS packets. Business risk depends on whether untrusted, partner, or carrier-adjacent networks can deliver MPLS traffic to those devices.
Exploitation context
The source bundle states exploitation requires sending a crafted MPLS packet to an affected Cisco SD-WAN or vManage device. CISA KEV is false, and no provided source states active exploitation or public weaponization.
Researcher notes
Evidence is limited to the CVE record and Cisco advisory reference in the bundle. Do not assume affected version ranges, fixed releases, or exploitation in the wild without consulting Cisco's advisory directly.
Mitigation direction
- Review Cisco's advisory for affected and fixed software guidance.
- Apply vendor-recommended Cisco SD-WAN updates where applicable.
- Limit MPLS packet exposure to trusted network paths where operationally feasible.
- Prioritize remediation on internet-adjacent or partner-reachable SD-WAN infrastructure.
Validation and detection
- Inventory Cisco SD-WAN and vManage deployments in production networks.
- Compare deployed versions and configurations against Cisco's advisory.
- Identify interfaces or paths that process MPLS traffic.
- Confirm whether untrusted networks can deliver MPLS packets to affected devices.
- Document remediation status and compensating network controls.
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-126: 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-2021-1614 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
- Medium
- CVSS
- 5.3 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
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:L/I:N/A:N3.91.4Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
5.3MediumVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Source materials
- CVE List V5 sourceCVE List V5
- 20210721 Cisco SD-WAN Software Information Disclosure 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.
Buffer Over-read
Buffer Over-read represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.