# CVE-2026-124560: D-Link DIR-878 HNAP prog.cgi GetCAPTCHAsetting heap-based overflow

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

A vulnerability was found in D-Link DIR-878 1.20B05. This affects the function GetCAPTCHAsetting of the file bin/prog.cgi of the component HNAP Handler. Performing a manipulation of the argument uid results in heap-based buffer overflow. The attack can be initiated remotely. The exploit has been made public and could be used. 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: 9.3 (critical); CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P; source: CNA: VulDB

- CVSS 3.1: 9.8 (critical); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:P/RL:X/RC:R; source: CNA: VulDB

- CVSS 3.0: 9.8 (critical); CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:P/RL:X/RC:R; source: CNA: VulDB

- CVSS 2.0: 10 (critical); AV:N/AC:L/Au:N/C:C/I:C/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-122, CWE-119

## Exploit evidence

- exploit: https://github.com/Zimo-666/DIR-878-cves/tree/main/01-captcha-uid-heap-overflow (CNA: VulDB)

## References

- https://vuldb.com/vuln/432892 (CNA: VulDB; vdb-entry, technical-description)

- https://vuldb.com/vuln/432892/cti (CNA: VulDB; signature, permissions-required)

- https://vuldb.com/cve/CVE-2026-124560 (CNA: VulDB; third-party-advisory)

- https://vuldb.com/submit/1035616 (CNA: VulDB; third-party-advisory)

- https://github.com/Zimo-666/DIR-878-cves/tree/main/01-captcha-uid-heap-overflow (CNA: VulDB; broken-link, exploit)

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

## Provenance

- CNA: VulDB: https://www.cve.org/CVERecord?id=CVE-2026-124560; retrieved 2026-11-09; source updated 2026-11-09

Revision: 43c1cd64956f100576764dccb73e9912c68a0dc14b4b3a26ff1aa55e79c0ba77

Canonical: https://y2.dev/cve/CVE-2026-124560

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