Security readout for executives and security teams
Plain-English summary
CVE-2021-1461 lets someone who already has Cisco SD-WAN Administrator-level access load a malicious software patch because patch image signatures were not properly verified. This is not a broad unauthenticated internet attack, but it matters because a compromised admin account could tamper with SD-WAN device software integrity.
Executive priority
Treat as a moderate-priority integrity risk. It is not reported as actively exploited in the supplied sources, but SD-WAN control infrastructure is sensitive and should be patched through normal expedited network maintenance.
Technical view
Cisco SD-WAN Software improperly verifies digital signatures for patch images, classified as CWE-347. An authenticated remote attacker with Administrator-level credentials could craft an unsigned patch that bypasses signature checks and boot a malicious patch image. CVSS 3.1 is 4.9 with high integrity impact and no confidentiality or availability impact listed.
Likely exposure
Exposure is limited to organizations running affected Cisco Catalyst SD-WAN Manager or Cisco SD-WAN vEdge Router versions listed in the advisory. Risk is concentrated around SD-WAN administrative interfaces and accounts with Administrator-level privileges.
Exploitation context
The source bundle does not show active exploitation and KEV is false. Exploitation requires authenticated remote access with Administrator-level credentials. Successful exploitation affects software integrity by allowing a malicious patch image to boot.
Researcher notes
Focus validation on signature verification bypass exposure in patch image handling. The main precondition is Administrator-level authentication, so credential compromise materially changes risk. Evidence is limited to the provided CVE and Cisco advisory data.
Mitigation direction
- Apply Cisco software updates that address this vulnerability.
- Do not rely on workarounds; Cisco states none address this issue.
- Inventory affected Catalyst SD-WAN Manager and vEdge Router versions.
- Restrict and review Administrator-level SD-WAN access.
- Check Cisco guidance for fixed release selection.
Validation and detection
- Confirm whether affected Cisco SD-WAN products and versions are deployed.
- Verify devices run Cisco software versions containing the fix.
- Review SD-WAN admin accounts for excessive or stale privileges.
- Inspect patch installation and administrative change records.
- Confirm monitoring covers SD-WAN software update activity.
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-347: 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-2021-1461 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
- 4.9 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:N/RL:X/RC:X/E:X
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:H/UI:N/S:U/C:N/I:H/A:N/RL:X/RC:X/E:X1.23.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
4.9MediumVector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:N/RL:X/RC:X/E:X
Source materials
- CVE List V5 sourceCVE List V5
- cisco-sa-sdwan-sigverbypass-gPYXd6MkCVE reference
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-xss-webui-gQLSFyPM</a></p><p>This advisory is part of the October 2021 release of the Cisco ASA, FTD, and FMC Security Advisory Bundled publication. For a complete list of the advisories and links to them, see <a href="https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-74773">Cisco Event Response: October 2021 Cisco ASA, FMC, and FTD Software Security Advisory Bundled PublicationCVE reference
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 Verification of Cryptographic Signature
Improper Verification of Cryptographic Signature represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.