# CVE-2026-5815 — D-Link DIR-645

> As of 2026-04-13, CVE-2026-5815 is a HIGH-severity vulnerability in D-Link DIR-645, CVSS v3.1 8.8, EPSS 0.9% (58.7th percentile). Threadlinqs Intelligence links 1 tracked threat campaign to CVE-2026-5815, most recently “TuxBot v3 Evolution: LLM-Assisted IoT Botnet Framework With a Broken Multi-CVE Exploit Chain”.

**Last updated:** 2026-04-13

## What is CVE-2026-5815?

A vulnerability was detected in D-Link DIR-645 1.01/1.02/1.03. Impacted is the function hedwigcgi_main of the file /cgi-bin/hedwig.cgi. The manipulation results in stack-based buffer overflow. The attack can be launched remotely. The exploit is now public and may be used. This vulnerability only affects products that are no longer supported by the maintainer.

The record classifies CVE-2026-5815 under weakness classes [CWE-121](https://intel.threadlinqs.com/cwe/CWE-121), [CWE-119](https://intel.threadlinqs.com/cwe/CWE-119). Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs low-privilege credentials, needs no user interaction, and has high impact on confidentiality, integrity, availability. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 203 days ago.

## Severity and exploitation probability

- **CVSS v3.1 base score:** 8.8 — HIGH (`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`)
- **CVSS v4.0 base score:** 8.7 (`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`)
- **EPSS (FIRST):** 0.9% probability of exploitation in the next 30 days, higher than 58.7% of all scored CVEs
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 8.8/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2026-04-08, last modified 2026-04-13

## Is CVE-2026-5815 being exploited?

Weaponised exploit code for CVE-2026-5815 is publicly available. 1 public proof-of-concept repository is tracked for this identifier. It currently carries a trending score of 28 in the Threadlinqs vulnerability feed.

- [trickest/cve](https://github.com/trickest/cve/blob/main/2026/CVE-2026-5815.md) (trickest)

## Affected products and versions

- [D-Link](https://intel.threadlinqs.com/vendors/d-link): DIR-645

## How to fix CVE-2026-5815

No vendor patch reference has been recorded for CVE-2026-5815 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.

## Threat activity tracking CVE-2026-5815

1 tracked threat in the Threadlinqs corpus references CVE-2026-5815, either in the campaign’s CVE list or as an indicator on the campaign record.

- [TuxBot v3 Evolution: LLM-Assisted IoT Botnet Framework With a Broken Multi-CVE Exploit Chain](https://intel.threadlinqs.com/threat/TL-2026-1366) — HIGH · 2026-07-15

## Sources

Enriched from CVE.org, FIRST EPSS, GitHub Security Advisories, public proof-of-concept repositories. Last verified by Threadlinqs on 2026-10-10.

**Exploit and proof of concept**

- [github.com — exploit](https://github.com/Pers1st0/CVE/blob/main/stack-based%20buffer%20overflow%20vulnerability%20exists%20in%20the%20hedwig.cgi%20of%20D-Link%20DIR-645.md#poc)

**Technical analysis**

- [vuldb.com — vdb entry](https://vuldb.com/vuln/356263)

**Third-party advisory**

- [vuldb.com — signature](https://vuldb.com/vuln/356263/cti)
- [vuldb.com — third party advisory](https://vuldb.com/submit/788298)

**Issue tracking and product pages**

- [dlink.com — product](https://www.dlink.com/)

**Other references**

- [github.com — related](https://github.com/Pers1st0/CVE/blob/main/stack-based%20buffer%20overflow%20vulnerability%20exists%20in%20the%20hedwig.cgi%20of%20D-Link%20DIR-645.md)

Canonical: https://intel.threadlinqs.com/cve/CVE-2026-5815
Full detection coverage and IOCs for threats exploiting CVE-2026-5815 via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp