# CVE-2026-91950: FreeRDP before 3.31.0 Out-of-Bounds Read via UINT32 Wraparound

> A malicious RDP server can trigger an out-of-bounds read via integer wraparound, causing client crashes or heap disclosure in FreeRDP.

- **Severity:** High 7.1 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/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:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 15 Sep 2026
- **Updated:** 15 Sep 2026
- **Also known as:** DEBIAN-CVE-2026-91950, GHSA-858j-6g95-r29w, GHSA-c5gr-hmqp-pwj4, UBUNTU-CVE-2026-91950

## What is CVE-2026-91950?

CVE-2026-91950 is a high-severity vulnerability in Freerdp Freerdp, published on 15 Sep 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

FreeRDP before 3.31.0 contains an out-of-bounds read vulnerability in the rdpdr_dump_packet function due to 32-bit unsigned integer wraparound in buffer bounds validation. A malicious RDP server can send a crafted RDPDR packet with computerNameLen set to 0xFFFFFFF0 to bypass bounds checks and trigger memory reads past the packet buffer, causing client crashes or heap disclosure in logs.

Weakness: CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2026-91950?

It affects 1 product.


Products: Freerdp Freerdp.

## How do I fix CVE-2026-91950?

Upgrade to a fixed version.

## Is CVE-2026-91950 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-91950 exists.

## 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-2026-91950 and fix it if it is affected.

What it is: CVE-2026-91950 is a high-severity vulnerability in Freerdp Freerdp, published on 15 Sep 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: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-91950 exists.

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-2026-91950/ (Markdown: https://insights.sbomify.com/CVE-2026-91950/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-91950
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-91950
- OSV: https://osv.dev/vulnerability/CVE-2026-91950

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-91950/
Summaries are generated and may contain mistakes; the official description above is the record.