# CVE-2025-10666: D-Link DIR-825 apply.cgi sub_4106d4 buffer overflow

> Remote attackers can trigger a buffer overflow in the D-Link DIR-825 router's apply.cgi script, potentially leading to code execution or denial of service.

- **Severity:** High 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`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 18 Sep 2025
- **Updated:** 3 Feb 2026
- **Also known as:** GHSA-xvh8-f5vg-49g2

## What is CVE-2025-10666?

CVE-2025-10666 is a high-severity memory corruption vulnerability in D-Link DIR-825, published on 18 Sep 2025. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

A security flaw has been discovered in D-Link DIR-825 up to 2.10. Affected by this vulnerability is the function sub_4106d4 of the file apply.cgi. The manipulation of the argument countdown_time results in buffer overflow. The attack can be executed remotely. The exploit has been released to the public and may be exploited. This vulnerability only affects products that are no longer supported by the maintainer.

Weakness: CWE-120 (Buffer Copy without Checking Size of Input), CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer)

## Which versions are affected by CVE-2025-10666?

It affects 1 product.


Products: Dlink Dir-825 Firmware.

## How do I fix CVE-2025-10666?

No fix has been published for CVE-2025-10666 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-10666 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-10666 exists.

Public exploit code:

- D-Link DIR-825 Rev.B 2.10 - Stack Buffer Overflow (DoS) (exploitdb)

## Other vulnerabilities in D-Link DIR-825

- [CVE-2022-47035](https://insights.sbomify.com/CVE-2022-47035/): Memory corruption in n/a (critical 9.8)
- [CVE-2021-46442](https://insights.sbomify.com/CVE-2021-46442/): Auth bypass in n/a (critical 9.8)
- [CVE-2025-7206](https://insights.sbomify.com/CVE-2025-7206/): D-Link DIR-825 httpd switch_language.cgi sub_410DDC stack-based overflow (critical 9.3)
- [CVE-2021-46441](https://insights.sbomify.com/CVE-2021-46441/): Command injection in n/a (high 8.8)
- [CVE-2020-10213](https://insights.sbomify.com/CVE-2020-10213/): Command injection in n/a (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-10666 and fix it if it is affected.

What it is: CVE-2025-10666 is a high-severity memory corruption vulnerability in D-Link DIR-825, published on 18 Sep 2025. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-10666 exists.

Affected product: D-Link DIR-825. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2025-10666/ (Markdown: https://insights.sbomify.com/CVE-2025-10666/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-10666
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-10666
- OSV: https://osv.dev/vulnerability/CVE-2025-10666

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-10666/
Summaries are generated and may contain mistakes; the official description above is the record.