Security readout for executives and security teams
Plain-English summary
A TOTOLINK T6 router running firmware 4.1.5cu.748_B20211015 may disclose its IP and port filtering rules without authentication. An attacker who can reach the management interface could learn sensitive network-control information. The supplied record rates this critical, although it does not establish real-world exploitation or identify a vendor fix.
Executive priority
Treat as an immediate inventory and exposure-reduction issue. Prioritize affected devices with internet-facing or broadly reachable management interfaces. Because no fix is identified in the supplied sources, assign ownership to obtain vendor guidance and set a replacement deadline if supported remediation is unavailable.
Technical view
CVE-2026-51660 is a CWE-284 access-control failure in getIpPortFilterRules. A crafted POST request to /cgi-bin/cstecgi.cgi reportedly returns filtering rules without authentication. CVSS 3.1 is 9.1: network-accessible, low complexity, no privileges or interaction. The stated integrity impact is not explained by the disclosed read behavior.
Likely exposure
Exposure is most likely where the affected T6 management endpoint is reachable from the internet, guest networks, or other untrusted segments. Devices restricted to trusted administration networks have reduced reachability, but remain vulnerable to attackers already present there. The supplied data names only firmware 4.1.5cu.748_B20211015; broader version exposure is unknown.
Exploitation context
The issue reportedly requires only network access and no authentication or user interaction. The source bundle marks it absent from KEV and provides no evidence of active exploitation. Public coordination references exist, but the supplied evidence does not establish exploit maturity, scanning activity, or weaponization.
Researcher notes
The record identifies an unauthenticated information-disclosure path, but its CVSS vector claims high confidentiality and integrity impact without describing rule modification. Do not infer write capability from the score alone. The supplied affected-product structure is incomplete, while the title specifically names TOTOLINK T6 firmware 4.1.5cu.748_B20211015. Patch status and adjacent affected versions remain unconfirmed.
Mitigation direction
- Inventory TOTOLINK T6 devices and confirm their installed firmware versions.
- Block internet and untrusted-segment access to router management interfaces.
- Permit administration only from a dedicated, trusted management network.
- Check TOTOLINK guidance for corrected firmware or vendor-approved mitigation.
- Consider replacing affected devices if no supported correction is available.
Validation and detection
- Confirm whether any T6 device runs firmware 4.1.5cu.748_B20211015.
- Review firewall rules controlling access to the management interface.
- Verify management endpoints are unreachable from internet and guest networks.
- Review logs for unexpected requests to /cgi-bin/cstecgi.cgi.
- After remediation, confirm the installed firmware matches current vendor guidance.
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-284: Authorization and privilege behavior lookup
Authorization weaknesses can support privilege escalation and valid-account review, depending on exploit path. 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-2026-51660 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
- 9.1 (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: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.
SSVC decision data
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:N3.95.2CISA-ADPVulnerability scoring details
Base CVSS 3.1 score
9.1CriticalVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- https://www.totolink.net/home/menu/detail/menu_listtpl/download/id/190/ids/36.htmlCVE reference, mitre
- https://www.totolink.net/CVE reference, mitre
- https://github.com/DarkBoulder/CVE-Vendor-Coordination/blob/main/TOTOLINK/README.mdCVE reference, mitre
- https://github.com/ShengWu00/CVE-Vendor-Coordination/blob/main/TOTOLINK/README.mdCVE reference, mitre
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 Access Control
Improper Access Control represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.