# CVE-2026-65976: Deskflow: Clipboard receiver can accumulate data beyond Deskflow's configured clipboard size limit

> A malicious peer can exhaust receiver memory by sending repeated clipboard data chunks, causing a denial of service in Deskflow.

- **Severity:** Medium 6.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 17 Aug 2026
- **Updated:** 18 Aug 2026
- **Also known as:** DEBIAN-CVE-2026-65976, GHSA-jf7g-qghg-p54x, UBUNTU-CVE-2026-65976

## What is CVE-2026-65976?

CVE-2026-65976 is a medium-severity denial of service vulnerability in deskflow, published on 17 Aug 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

Deskflow is a keyboard and mouse sharing app. From 1.17.0 until continuous build 1.26.0.300, a connected peer can send repeated DCLP DataChunk messages to ClipboardChunk::assemble() in src/lib/deskflow/ClipboardChunk.cpp, causing the server path in src/lib/server/ClientProxy1_6.cpp or client path in src/lib/client/ServerProxy.cpp to append data beyond the DataStart declared size and configured clipboard limit before DataEnd validation, exhausting receiver memory. This issue is fixed in continuous build 1.26.0.300.

Weakness: CWE-400 (Uncontrolled Resource Consumption)

## Which versions are affected by CVE-2026-65976?


## How do I fix CVE-2026-65976?

Upgrade to a fixed version.

## Is CVE-2026-65976 being exploited?

There is no known exploitation of CVE-2026-65976 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-65976 and fix it if it is affected.

What it is: CVE-2026-65976 is a medium-severity denial of service vulnerability in deskflow, published on 17 Aug 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-65976 in the wild and no public exploit code.

Affected product: deskflow. 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-2026-65976/ (Markdown: https://insights.sbomify.com/CVE-2026-65976/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-65976
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-65976
- OSV: https://osv.dev/vulnerability/CVE-2026-65976

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-65976/
Summaries are generated and may contain mistakes; the official description above is the record.