Security readout for executives and security teams
Plain-English summary
CVE-2026-0839 affects UTT 进取 520W firmware version 1.7.7-180627. A remote, authenticated attacker could trigger a buffer overflow in the APSecurity interface via the wepkey1 argument, potentially gaining full control of the device. Public proof-of-concept material is referenced, but there is no KEV listing or cited evidence of active exploitation.
Executive priority
Treat as urgent for environments using this router model. The combination of critical impact, network reachability, and public exploit material warrants rapid exposure review and containment. If affected devices cannot be patched, isolate or replace them based on business criticality.
Technical view
The vulnerability is a strcpy-based buffer overflow in /goform/APSecurity, mapped to CWE-119 and CWE-120. The CVSS 2.0 vector is AV:N/AC:L/Au:S/C:C/I:C/A:C with score 9.0. Sources state the exploit is publicly available and vendor contact received no response. No official patch or workaround is identified in the provided sources.
Likely exposure
Exposure is limited to UTT 进取 520W devices running firmware 1.7.7-180627, especially if the management interface is reachable by untrusted networks or users. Authentication is indicated as required, reducing drive-by exposure but not insider, stolen-credential, or weak-password risk.
Exploitation context
The issue is remotely reachable and low complexity after authentication. Public exploit material is cited, increasing practical risk. However, the supplied sources do not show confirmed real-world exploitation, and the CVE is not listed as KEV in the provided data.
Researcher notes
Evidence comes mainly from VulDB/CVE metadata and a public GitHub reference. The vendor reportedly did not respond, and no official fix is named. Avoid assuming broader product impact beyond UTT 进取 520W 1.7.7-180627 unless independently verified.
Mitigation direction
- Identify any UTT 进取 520W devices running firmware 1.7.7-180627.
- Restrict management access to trusted administrative networks only.
- Disable external exposure of the device administration interface where possible.
- Review vendor channels for firmware updates or official guidance.
- Use strong, unique administrator credentials and remove unnecessary accounts.
- Prioritize replacement or isolation if no vendor fix is available.
Validation and detection
- Inventory edge and network devices for UTT 进取 520W models.
- Confirm firmware version against 1.7.7-180627.
- Check whether /goform/APSecurity is reachable from untrusted networks.
- Review logs for unusual authenticated administration activity.
- Monitor VulDB, CVE, and vendor sources for updated remediation details.
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-2026-0839 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.
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.
AV:N/AC:L/Au:S/C:C/I:C/A:C/E:POC/RL:ND/RC:UR810Primary CVE scoreVulnerability scoring details
Base CVSS 2.0 score
9CriticalVector: AV:N/AC:L/Au:S/C:C/I:C/A:C/E:POC/RL:ND/RC:UR
Source materials
- CVE List V5 sourceCVE List V5
- VDB-340439 | UTT 进取 520W APSecurity strcpy buffer overflowCVE reference · vdb-entry, technical-description
- VDB-340439 | CTI Indicators (IOB, IOC, IOA)CVE reference · signature, permissions-required
- Submit #729028 | UTT 进取 520W v3v1.7.7-180627 Buffer OverflowCVE reference · third-party-advisory
- https://github.com/GUOTINGTING2297/cve/blob/main/1234/29.mdCVE reference · exploit
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.