# CVE-2026-41521: xrdp: lib_framebuffer_update Has Integer Overflow Heap Info Leak & ASLR Bypass

> A malicious remote VNC server can trigger an integer overflow in xrdp to leak heap memory or crash the service via crafted image dimensions.

- **Severity:** High 8.2 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 20 Jul 2026
- **Updated:** 20 Jul 2026
- **Also known as:** DEBIAN-CVE-2026-41521, GHSA-v8w6-pf78-9458, UBUNTU-CVE-2026-41521

## What is CVE-2026-41521?

CVE-2026-41521 is a high-severity vulnerability in neutrinolabs xrdp, published on 20 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

xrdp is an open source RDP server. Versions 0.10.6 and prior contain an integer overflow vulnerability when processing screen update messages within the vnc-any connection mode. A malicious remote VNC server can send crafted image dimensions that cause an integer overflow during memory buffer size calculation, resulting in an undersized allocation. Subsequent processing of the incoming image data using the original oversized parameters leads to an out-of-bounds read. An unauthenticated remote attacker could exploit this flaw to disclose sensitive information from the heap memory or cause a denial of service (DoS) via a process crash. This issue has been fixed in version 0.10.6.1.

Weakness: CWE-190 (Integer Overflow or Wraparound)

## Which versions are affected by CVE-2026-41521?

It affects 1 product.


Products: Neutrinolabs Xrdp.

## How do I fix CVE-2026-41521?

Upgrade to a fixed version.

## Is CVE-2026-41521 being exploited?

There is no known exploitation of CVE-2026-41521 in the wild and no public exploit code.

## Other vulnerabilities in neutrinolabs xrdp

- [CVE-2026-41252](https://insights.sbomify.com/CVE-2026-41252/): xrdp: lib_palette_update Heap Buffer Overflow & RCE (critical 9.8)
- [CVE-2026-32105](https://insights.sbomify.com/CVE-2026-32105/): xrdp: RDP MAC signature (dataSignature) never verified on receive — integrity bypass in non-TLS mode (critical 9.3)
- [CVE-2026-44178](https://insights.sbomify.com/CVE-2026-44178/): xrdp: Channel Data Forwarding Fixed-Size Buffer Overflow (high 8.8)
- [CVE-2026-32107](https://insights.sbomify.com/CVE-2026-32107/): xrdp: Fail-open privilege drop in sesexec — child processes may execute as root if setuid fails (high 8.8)
- [CVE-2026-33689](https://insights.sbomify.com/CVE-2026-33689/): xrdp: Pre-authentication out-of-bounds reads in channel parsers (high 8.7)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-41521 and fix it if it is affected.

What it is: CVE-2026-41521 is a high-severity vulnerability in neutrinolabs xrdp, published on 20 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-41521 in the wild and no public exploit code.

Affected product: neutrinolabs xrdp. 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-2026-41521/ (Markdown: https://insights.sbomify.com/CVE-2026-41521/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-41521
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-41521
- OSV: https://osv.dev/vulnerability/CVE-2026-41521

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-41521/
Summaries are generated and may contain mistakes; the official description above is the record.