# CVE-2026-124561: D-Link DIR-878 HNAP prog.cgi SetVLANSettings stack-based overflow

Status: published. Published: 2026-11-09. Updated: 2026-11-09.

A vulnerability was determined in D-Link DIR-878 1.20B05. This impacts the function SetVLANSettings of the file prog.cgi of the component HNAP Handler. Executing a manipulation of the argument VID can lead to stack-based buffer overflow. The attack can be launched remotely. The exploit has been publicly disclosed and may be utilized. This vulnerability only affects products that are no longer supported by the maintainer.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- D-Link / DIR-878: 1.20B05 (affected). Source: CNA: VulDB

## Severity and prioritization

- CVSS 4.0: 8.7 (high); CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P; source: CNA: VulDB

- CVSS 3.1: 7.5 (high); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:X/RC:R; source: CNA: VulDB

- CVSS 3.0: 7.5 (high); CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:X/RC:R; source: CNA: VulDB

- CVSS 2.0: 7.8 (high); AV:N/AC:L/Au:N/C:N/I:N/A:C/E:POC/RL:ND/RC:UR; source: CNA: VulDB

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-121, CWE-119

## Exploit evidence

- exploit: https://github.com/Zimo-666/DIR-878-cves/tree/main/03-settriggeradic-vlan-stack-overflow (CNA: VulDB)

## References

- https://vuldb.com/vuln/432893 (CNA: VulDB; vdb-entry, technical-description)

- https://vuldb.com/vuln/432893/cti (CNA: VulDB; signature, permissions-required)

- https://vuldb.com/cve/CVE-2026-124561 (CNA: VulDB; third-party-advisory)

- https://vuldb.com/submit/1035617 (CNA: VulDB; third-party-advisory)

- https://github.com/Zimo-666/DIR-878-cves/tree/main/03-settriggeradic-vlan-stack-overflow (CNA: VulDB; broken-link, exploit)

- https://www.dlink.com/ (CNA: VulDB; product)

## Provenance

- CNA: VulDB: https://www.cve.org/CVERecord?id=CVE-2026-124561; retrieved 2026-11-09; source updated 2026-11-09

Revision: 2a327fe8bb615e752b93e672a6ab0af74e6f53a1f3a5d47ce21173168fff23b1

Canonical: https://y2.dev/cve/CVE-2026-124561

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