Security readout for executives and security teams
Plain-English summary
This is a critical memory-safety flaw reported in a Tenda W20E router firmware version. A remote, unauthenticated attacker could potentially compromise confidentiality, integrity, and availability if a vulnerable device is reachable. The source bundle does not identify a vendor patch or confirm active exploitation.
Executive priority
Treat as urgent for any exposed or business-critical Tenda W20E deployment. The score is critical and the attack model is remote and unauthenticated, but available sources do not prove exploitation in the wild or identify a specific patch.
Technical view
CVE-2022-40868 describes a stack overflow/CWE-787 issue in the Tenda W20E V15.11.0.6 formDelDhcpRule function associated with DHCP rule deletion handling. CVSS 3.1 is 9.8 with network attack vector, low complexity, no privileges, and no user interaction.
Likely exposure
Exposure appears limited to Tenda W20E routers running the specific V15.11.0.6 firmware string named in the CVE. The bundle provides no CPEs or broader affected-version matrix. Internet-facing or untrusted-network reachable administration surfaces would raise urgency.
Exploitation context
The CVSS vector supports high theoretical risk: remote, unauthenticated, low-complexity exploitation with high impact. The CVE is not marked KEV in the bundle, and no cited source confirms active exploitation. A public GitHub reference exists, so defenders should assume details are discoverable.
Researcher notes
The source evidence is narrow: CVE metadata, CVSS vector, CWE-787, and one GitHub vulnerability reference. Affected product metadata is incomplete in the bundle, so avoid extrapolating beyond the named Tenda W20E firmware until vendor advisories confirm scope.
Mitigation direction
- Inventory Tenda W20E devices and record exact firmware versions.
- Check Tenda or device supplier guidance for corrected firmware or replacement advice.
- Restrict router administration access to trusted management networks only.
- Remove any unnecessary internet exposure for affected router interfaces.
- Monitor router logs and network telemetry for unusual management activity.
Validation and detection
- Confirm whether any deployed router matches the named Tenda W20E firmware string.
- Review external exposure for router management and related administrative services.
- Check vulnerability management tools for CVE-2022-40868 coverage.
- Verify whether vendor documentation names a patched firmware for this model.
- Document compensating controls where patch status remains unknown.
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-787: 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-2022-40868 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
- Critical
- CVSS
- 9.8 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/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:H/I:H/A:H3.95.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
9.8CriticalVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/CPSeek/Router-vuls/blob/main/Tenda/W20E/formDelDhcpRule.mdCVE reference · x_refsource_MISC
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.
Out-of-bounds Write
Out-of-bounds Write represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.