# CVE-2026-116785: FreeSWITCH: Pre-authentication heap out-of-bounds write in mod_xml_rpc WebSocket frame length handling


- **Severity:** Critical 9.1 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Fix available:** No
- **Published:** 5 Nov 2026
- **Updated:** 9 Nov 2026
- **Also known as:** GHSA-jj89-q47c-gh94

## What is CVE-2026-116785?

CVE-2026-116785 is a critical vulnerability in signalwire freeswitch, published on 5 Nov 2026. 

### Official description

FreeSWITCH is a Software Defined Telecom Stack enabling the digital transformation from proprietary telecom switches to a software implementation that runs on any commodity hardware. Prior to 1.11.2, ws_read_frame() decoded a WebSocket frame's 64-bit extended payload length with a 32-bit byte swap and narrowed the result into a signed length. A value whose surviving low word became negative bypassed the signed size check and was reinterpreted as an enormous unsigned count, causing client bytes to overwrite memory beyond the 64 KiB receive buffer. Any client completing a /socket WebSocket upgrade on an enabled mod_xml_rpc endpoint reached the parser before HTTP authentication; both the module and WebSocket endpoint are disabled by default. The heap overwrite can corrupt connection pointers and crash FreeSWITCH, ending every concurrent session, although remote code execution has not been demonstrated. This issue is fixed in version 1.11.2.

Weakness: CWE-787 (Out-of-bounds Write), CWE-681 (Incorrect Conversion between Numeric Types), CWE-122 (Heap-based Buffer Overflow)

## Which versions are affected by CVE-2026-116785?

It affects 1 product.


Products: Freeswitch.

## How do I fix CVE-2026-116785?

No fix has been published for CVE-2026-116785 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-116785 being exploited?

There is no known exploitation of CVE-2026-116785 in the wild and no public exploit code.

## Other vulnerabilities in signalwire freeswitch

- [CVE-2026-116779](https://insights.sbomify.com/CVE-2026-116779/): SignalWire FreeSwitch Code Injection (critical 9.8, exploited in the wild)
- [CVE-2026-49841](https://insights.sbomify.com/CVE-2026-49841/): FreeSWITCH: Pre-authentication heap buffer overflow in `mod_verto` HTTP POST body read (critical 9.8)
- [CVE-2019-19492](https://insights.sbomify.com/CVE-2019-19492/): FreeSWITCH 1.6.10 through 1.10.1 has a default password in event_socket.conf.xml. (critical 9.8)
- [CVE-2026-116790](https://insights.sbomify.com/CVE-2026-116790/): FreeSWITCH: Inbound ICE connectivity checks are accepted without verifying STUN MESSAGE-INTEGRITY (critical 9.1)
- [CVE-2026-49840](https://insights.sbomify.com/CVE-2026-49840/): FreeSWITCH: Pre-authentication heap buffer overflow in libesl `Content-Length` parsing (critical 9.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-116785 and fix it if it is affected.

What it is: CVE-2026-116785 is a critical vulnerability in signalwire freeswitch, published on 5 Nov 2026. 
Exploitation: There is no known exploitation of CVE-2026-116785 in the wild and no public exploit code.

Affected product: signalwire freeswitch. 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-2026-116785/ (Markdown: https://insights.sbomify.com/CVE-2026-116785/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-116785
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-116785
- OSV: https://osv.dev/vulnerability/CVE-2026-116785

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-116785/
Summaries are generated and may contain mistakes; the official description above is the record.