# CVE-2026-68579: FreeRDP before 3.30.0 Heap Overflow via CliprdrStream_Read

> A malicious RDP server can trigger a heap overflow in the FreeRDP client during clipboard paste operations, potentially allowing remote code execution.

- **Severity:** High 8.7 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 2 Aug 2026
- **Updated:** 3 Aug 2026
- **Also known as:** DEBIAN-CVE-2026-68579, GHSA-m4j8-6wj9-56fg, UBUNTU-CVE-2026-68579

## What is CVE-2026-68579?

CVE-2026-68579 is a high-severity memory corruption vulnerability in Freerdp Freerdp, published on 2 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

FreeRDP before 3.30.0 (<= 3.29.0) contains a heap-based buffer overflow in the Windows clipboard client's CliprdrStream_Read function (client/Windows/wf_cliprdr.c). When an OLE paste consumer (e.g. explorer.exe) calls IStream::Read with a fixed-size buffer of cb bytes, CliprdrStream_Read requests file contents from the RDP server and then copies the response into the caller's buffer using the server-supplied length (req_fsize) instead of cb. A malicious or compromised RDP server can return an oversized CB_FILECONTENTS_RESPONSE, causing an out-of-bounds write of attacker-controlled data into the paste consumer's heap buffer when a user pastes server-offered clipboard file contents.

Weakness: CWE-787 (Out-of-bounds Write)

## Which versions are affected by CVE-2026-68579?

It affects 1 product.


Products: Freerdp Freerdp.

## How do I fix CVE-2026-68579?

Upgrade to a fixed version.

## Is CVE-2026-68579 being exploited?

There is no known exploitation of CVE-2026-68579 in the wild and no public exploit code.

## Other vulnerabilities in Freerdp Freerdp

- [CVE-2021-37594](https://insights.sbomify.com/CVE-2021-37594/): Other in n/a (critical 9.8)
- [CVE-2021-37595](https://insights.sbomify.com/CVE-2021-37595/): Other in n/a (critical 9.8)
- [CVE-2026-67305](https://insights.sbomify.com/CVE-2026-67305/): FreeRDP Windows Client before 3.29.0 Heap Buffer Overflow via Cliprdr (critical 9.4)
- [CVE-2026-66402](https://insights.sbomify.com/CVE-2026-66402/): FreeRDP before 3.29.0 TLS Certificate Identity Validation Bypass (critical 9.3)
- [CVE-2026-67289](https://insights.sbomify.com/CVE-2026-67289/): FreeRDP before 3.29.0 HTTP Proxy Request Injection via Redirection (critical 9.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-68579 and fix it if it is affected.

What it is: CVE-2026-68579 is a high-severity memory corruption vulnerability in Freerdp Freerdp, published on 2 Aug 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-2026-68579 in the wild and no public exploit code.

Affected product: Freerdp Freerdp. 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-2026-68579/ (Markdown: https://insights.sbomify.com/CVE-2026-68579/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-68579
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-68579
- OSV: https://osv.dev/vulnerability/CVE-2026-68579

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-68579/
Summaries are generated and may contain mistakes; the official description above is the record.