Security readout for executives and security teams
Plain-English summary
This CVE describes a critical flaw in Tenda W20E router firmware V15.11.0.6. A network attacker may crash the device or potentially run code by abusing port-mapping request handling. The CVE data does not name a vendor patch, and the structured affected-product metadata is incomplete.
Executive priority
Treat this as a high-priority edge-device risk if Tenda W20E routers are present. The main business concern is compromise or outage of network routing equipment. Prioritize exposure reduction immediately while confirming whether vendor remediation exists.
Technical view
The reported issue is a stack overflow in formSetPortMapping for POST requests to goform/setPortMapping/. The CVSS 3.1 score is 9.8 because attack is network-accessible, low complexity, unauthenticated, and requires no user interaction. Impact is listed as high for confidentiality, integrity, and availability.
Likely exposure
Exposure is most likely where Tenda W20E V15.11.0.6 devices are deployed and their web management or relevant port-mapping interface is reachable from untrusted networks. The CVE record’s structured affected field is incomplete, so product identification should rely on asset inventory and firmware verification.
Exploitation context
The source bundle supports possible denial of service or remote code execution. It does not show CISA KEV listing or any cited evidence of active exploitation. Public reference material appears to include vulnerability details, but no source in the bundle confirms real-world exploitation.
Researcher notes
The CVE record identifies CWE-787 and a specific vulnerable function and request path. NVD-style affected metadata is weak, listing vendor and product as n/a. Analysis should preserve that uncertainty and avoid expanding scope beyond Tenda W20E V15.11.0.6 without additional evidence.
Mitigation direction
- Check Tenda’s current guidance for W20E V15.11.0.6 and apply any vendor-provided firmware or workaround.
- Block Internet access to router management and port-mapping administration interfaces.
- Limit management access to trusted administrative networks or VPN paths.
- Disable unnecessary port-mapping features where operationally feasible.
- Replace unsupported or unpatchable affected devices with supported equipment.
Validation and detection
- Inventory Tenda W20E devices and verify firmware versions against V15.11.0.6.
- Confirm management interfaces are not reachable from the Internet or guest networks.
- Review firewall rules for exposure of router administration services.
- Check device logs for unexplained crashes, reboots, or unexpected port-mapping changes.
- Track the CVE record and vendor channels for patch or mitigation updates.
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 lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2022-40855 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/formSetPortMapping.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.