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CVE Record

CVE-2026-9428: Tenda F1202 PPTPUserSetting fromPPTPUserSetting stack-based overflow

A vulnerability has been found in Tenda F1202 1.2.0.20(408). Affected is the function fromPPTPUserSetting of the file /goform/PPTPUserSetting. Such manipulation of the argument delno leads to stack-based buffer overflow. The attack may be performed from remote. The exploit has been disclosed to the public and may be used.

CriticalCVSS 9Not KEV-listed Updated
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Glexia's Take critical

Analyst readout for executives and security teams

Plain-English summary

CVE-2026-9428 affects Tenda F1202 routers running firmware 1.2.0.20(408). A flaw in the PPTP user settings handler can cause a stack-based buffer overflow after authenticated remote access. Public exploit information is reported, but the sources do not show confirmed active exploitation.

Executive priority

Treat this as urgent for any deployed Tenda F1202 routers, especially if administration is remotely reachable. Prioritize inventory, management-interface isolation, and vendor guidance review before assuming a patch exists.

Technical view

VulDB describes a stack-based buffer overflow in fromPPTPUserSetting within /goform/PPTPUserSetting, triggered through the delno argument. The CVSS v2 vector is AV:N/AC:L/Au:S/C:C/I:C/A:C, indicating remote, low-complexity exploitation requiring authentication, with full confidentiality, integrity, and availability impact.

Likely exposure

Exposure is limited to Tenda F1202 devices on firmware 1.2.0.20(408) where authenticated users can reach the router management function for PPTP user settings. Internet-reachable administration would materially increase risk.

Exploitation context

The bundle states exploit details have been publicly disclosed and may be used. CISA KEV status is false, and no cited source confirms active exploitation in the wild. Authentication is required according to the supplied CVSS vector and CTI reference tagging.

Researcher notes

Evidence identifies CWE-119 and CWE-121 with public exploit disclosure, but does not provide confirmed exploitation or a vendor fix. The affected surface is authenticated remote access to /goform/PPTPUserSetting on firmware 1.2.0.20(408). Confidence is bounded by reliance on VulDB and provided CVE metadata.

Mitigation direction

  • Inventory Tenda F1202 routers and identify firmware 1.2.0.20(408).
  • Check Tenda and VulDB guidance for fixed firmware or vendor mitigations.
  • Restrict router administration to trusted management networks only.
  • Remove internet exposure for router management interfaces.
  • Limit administrative accounts that can modify PPTP user settings.
  • Monitor for suspicious access to PPTPUserSetting where logging exists.

Validation and detection

  • Confirm whether any Tenda F1202 devices run firmware 1.2.0.20(408).
  • Verify management interfaces are not reachable from untrusted networks.
  • Review user accounts with router administration or PPTP settings access.
  • Check available logs for unusual PPTP settings changes or access.
  • Track CVE and vendor pages for updated remediation information.
Prepared
Confidence
medium
Sources
7

Public sources used

Based on public source material and reviewed before publication.

Potential ATT&CK relevance

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 · low confidence lookup

CWE-119: 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 lookup
cwe · low confidence lookup

CWE-121: 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 lookup
cve · low confidence lookup

CVE-2026-9428 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

Open ATT&CK lookup
Vulnerability profile CVE Program record
Severity
Critical
CVSS
9 (2.0)
Known Exploited
No
Published

Vector: AV:N/AC:L/Au:S/C:C/I:C/A:C/E:POC/RL:ND/RC:UR

Official CVE source material

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.

4 CVSS vectors
6 Timeline events
0 ADP providers
6 Source links

CVSS vector scores

4 official scores

We 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.

Score Version Severity Vector Exploit Impact Source
9 CVSS 2.0 Critical AV:N/AC:L/Au:S/C:C/I:C/A:C/E:POC/RL:ND/RC:UR 8 10 VulDB
8.8 CVSS 3.1 High CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/RL:X/RC:R 2.8 5.9 VulDB
8.8 CVSS 3.0 High CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/RL:X/RC:R 2.8 5.9 VulDB
8.7 CVSS 4.0 High CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P — — VulDB

Vulnerability scoring details

Base CVSS 4.0 score

8.7 High
CVSS 4.0 vector shape for CVE-2026-9428 Attack VectorAttack ComplexityAttack RequirementsPrivileges RequiredUser InteractionVS ConfidentialityVS IntegrityVS AvailabilitySS ConfidentialitySS IntegritySS Availability

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Attack Requirements
NonePresent
Privileges Required
NoneLowHigh
User Interaction
NonePassiveActive
VS Confidentiality
HighLowNone
VS Integrity
HighLowNone
VS Availability
HighLowNone
SS Confidentiality
HighLowNone
SS Integrity
HighLowNone
SS Availability
HighLowNone

Vulnerability timeline

Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.

  1. Source timeline VulDB

    Advisory disclosed

  2. Source timeline VulDB

    VulDB entry created

  3. CVE reserved CVE Program

    The CVE ID was reserved by the assigning CNA.

  4. Source timeline VulDB

    VulDB entry last update

  5. CVE published CVE Program

    The CVE record was published.

  6. CVE updated CVE Program

    The CVE record metadata indicates this as the latest update time.

Source materials

Affected products

Products and packages named in the record

Vendor Product Version / package Status
Tenda F1202 1.2.0.20(408) Listed
Weakness

CWE details

CWE-119CWE-121

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.

CWE-119 · source CWE mapping

Improper Restriction of Operations within the Bounds of a Memory Buffer

Improper Restriction of Operations within the Bounds of a Memory Buffer represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.

Open CWE intelligence Same-CWE CVEs
CWE-121 · source CWE mapping

Stack-based Buffer Overflow

Stack-based Buffer Overflow represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.

Open CWE intelligence Same-CWE CVEs