# CVE-2026-75118: http_gdpr_decrypt Pre-Authentication Stack-Based Buffer Overflow

> An adjacent unauthenticated attacker can trigger a stack-based buffer overflow in the router's web interface, potentially achieving arbitrary code execution or causing a service crash.

- **Severity:** High 8.7 (`CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 28 Aug 2026
- **Updated:** 1 Sep 2026
- **Also known as:** GHSA-p3fv-q9vc-j25p

## What is CVE-2026-75118?

CVE-2026-75118 is a high-severity memory corruption vulnerability in TP-Link Systems Inc. TL-MR100 v3.20, published on 28 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A pre-authentication stack-based buffer overflow vulnerability exists in the http_gdpr_decrypt function of TL-MR100 V3.20 due to insufficient bounds checking of encrypted requests to the /cgi/login endpoint. An adjacent unauthenticated attacker with access to the router's web management interface can trigger memory corruption and potentially achieve arbitrary code execution.

Successful exploitation can overwrite saved control-flow data on the httpd process stack prior to authentication, resulting in a service crash or potential arbitrary code execution in the context of the affected process.

Weakness: CWE-121 (Stack-based Buffer Overflow)

## Which versions are affected by CVE-2026-75118?


## How do I fix CVE-2026-75118?

No fix has been published for CVE-2026-75118 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-75118 being exploited?

There is no known exploitation of CVE-2026-75118 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-75118 and fix it if it is affected.

What it is: CVE-2026-75118 is a high-severity memory corruption vulnerability in TP-Link Systems Inc. TL-MR100 v3.20, published on 28 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-75118 in the wild and no public exploit code.

Affected product: TP-Link Systems Inc. TL-MR100 v3.20. 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-2026-75118/ (Markdown: https://insights.sbomify.com/CVE-2026-75118/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-75118
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-75118
- OSV: https://osv.dev/vulnerability/CVE-2026-75118

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-75118/
Summaries are generated and may contain mistakes; the official description above is the record.