Security readout for executives and security teams
Plain-English summary
CVE-2026-3378 is a critical buffer overflow in Tenda F453 firmware 1.0.0.3. A remote attacker who can access the QoS settings function may be able to crash or take control of the device. Public exploit material is available, but the provided sources do not show confirmed active exploitation.
Executive priority
Treat this as urgent for any deployed Tenda F453 devices. The risk is highest where management access is internet-facing or broadly reachable. Prioritize discovery, access restriction, and vendor update checks because public exploit information exists and no fix is identified in the supplied sources.
Technical view
The flaw affects the fromqossetting function in /goform/qossetting. Manipulating the qos argument can trigger a buffer overflow, mapped to CWE-119 and CWE-120. The CVSS v2 vector is 9.0 with network access, low complexity, and single authentication required. VulDB reports exploit disclosure and no remediation listed.
Likely exposure
Organizations using Tenda F453 firmware 1.0.0.3 are potentially exposed, especially if the device management interface is reachable from untrusted networks. Exposure depends on whether access to /goform/qossetting requires valid credentials and whether management access is restricted.
Exploitation context
The source bundle states the attack can be launched remotely and that exploit code has been published. CVSS indicates authentication is required. CISA KEV status is false in the provided data, so active exploitation should not be assumed from these sources.
Researcher notes
Do not assume unauthenticated exploitation; the CVSS vector includes Au:S. The public advisory identifies the vulnerable endpoint and parameter, but the provided bundle does not confirm a patch, active exploitation, or affected firmware beyond 1.0.0.3.
Mitigation direction
- Identify any Tenda F453 devices and record firmware versions.
- Restrict management access to trusted administrative networks only.
- Disable remote administration if it is not required.
- Check Tenda and VulDB for firmware updates or official guidance.
- Replace or isolate affected devices if no vendor fix is available.
Validation and detection
- Inventory network edge and branch devices for Tenda F453 models.
- Confirm whether firmware version 1.0.0.3 is installed.
- Review exposure of the device management interface.
- Check logs for unusual QoS settings changes or failed access attempts.
- Monitor vendor advisories for a fixed firmware release.
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-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 lookupCWE-120: 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-2026-3378 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 (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
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
4 official scoresWe 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.
AV:N/AC:L/Au:S/C:C/I:C/A:C/E:POC/RL:ND/RC:UR810VulDBCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/RL:X/RC:R2.85.9VulDBCVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/RL:X/RC:R2.85.9VulDBCVSS: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——VulDBVulnerability scoring details
Base CVSS 4.0 score
8.7HighVector: 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
Base CVSS 3.1 score
8.8HighVector: 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
Base CVSS 3.0 score
8.8HighVector: 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
Base CVSS 2.0 score
9CriticalVector: AV:N/AC:L/Au:S/C:C/I:C/A:C/E:POC/RL:ND/RC:UR
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- Source timelineVulDB
Advisory disclosed
- Source timelineVulDB
VulDB entry created
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- Source timelineVulDB
VulDB entry last update
- 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
- VDB-348263 | Tenda F453 qossetting fromqossetting buffer overflowCVE reference, VulDB · vdb-entry, technical-description
- VDB-348263 | CTI Indicators (IOB, IOC, IOA)CVE reference, VulDB · signature, permissions-required
- Submit #759625 | Tenda F453 v1.0.0.3 Buffer Access Using Size of Source BufferCVE reference, VulDB · third-party-advisory
- https://github.com/Litengzheng/vul_db/blob/main/F453/vul_78/README.mdCVE reference, VulDB · exploit
- https://www.tenda.com.cn/CVE reference, VulDB · product
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 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.
Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.