PatchSiren

PatchSiren cyber security CVE debrief

CVE-2026-5815 D-Link CVE debrief

A stack-based buffer overflow vulnerability exists in the hedwigcgi_main function of the /cgi-bin/hedwig.cgi file in D-Link DIR-645 versions 1.01, 1.02, and 1.03. This issue allows remote attackers to exploit the vulnerability. The exploit is now public and may be used. However, detailed information about the exploit and its impact is limited. The vulnerability only affects products that are no longer supported by the maintainer.

Vendor
D-Link
Product
DIR-645
CVSS
HIGH 7.4
CISA KEV
Not listed in stored evidence
Original CVE published
2026-04-09
Original CVE updated
2026-07-24
Advisory published
2026-04-09
Advisory updated
2026-07-24

Who should care

Organizations and individuals using D-Link DIR-645 versions 1.01, 1.02, and 1.03 should be aware of this vulnerability. Since the affected products are no longer supported, users may need to consider alternative solutions or compensating controls to mitigate the risk.

Technical summary

The CVE-2026-5815 vulnerability is a stack-based buffer overflow issue in the hedwigcgi_main function of the /cgi-bin/hedwig.cgi file in D-Link DIR-645 versions 1.01, 1.02, and 1.03. The Common Vulnerability Scoring System (CVSS) score for this vulnerability is 7.4, indicating a high severity. The CVSS vector is 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/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X.

Defensive priority

High priority should be given to addressing this vulnerability, especially since the affected products are no longer supported by the vendor. Users should consider immediate defensive actions to mitigate potential risks.

Recommended defensive actions

  • Inventory and assess the vulnerability of D-Link DIR-645 devices in your environment.
  • Consider replacing affected devices with supported alternatives.
  • Implement compensating controls, such as network segmentation or access restrictions, to reduce the attack surface.
  • Monitor for potential exploitation attempts and anomalous activity.
  • Review and update incident response plans to address potential exploitation of this vulnerability.

Evidence notes

The CVE record was published on 2026-04-09T00:16:20.863Z and was last modified on 2026-07-24T09:10:00.153Z. The NVD entry is currently Deferred. The vulnerability details are based on limited information from the CVE and NVD records, as well as references from Vuldb.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-5815 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-5815

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-5815 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-5815

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.