# CVE-2026-61776: NVIDIA Megatron Bridge deserialization of untrusted data

Source: https://junglewise.ai/threats/cve-2026-61776-nvidia-megatron-bridge-deserialization-of-untrusted-data  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-01. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-61776 · Severity: high · CVSS 7.8 · Published 2026-09-01

NVIDIA Megatron Bridge is a library used for distributed training of large neural networks across multiple GPUs and nodes. A deserialization vulnerability allows an attacker to execute arbitrary code, modify data, or access sensitive information when untrusted serialized data is processed by the library.

Technologies: [Nvidia Megatron-Bridge](https://junglewise.ai/threats/technologies/megatron-bridge), [Nvidia Nemo Megatron Bridge](https://junglewise.ai/threats/technologies/nemo-megatron-bridge). Vendors: [Nvidia](https://junglewise.ai/threats/vendors/nvidia).

## Quick answers

**Is CVE-2026-61776 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-61776 being exploited in the wild.

**How severe is CVE-2026-61776?** High severity, with a CVSS score of 7.8, published 1 September 2026.

**Which products and versions are affected?** NVIDIA Megatron Bridge.

**Is there a fix for CVE-2026-61776?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-61776 attacked?** It is attacked over the network or with local access.

**Am I affected by CVE-2026-61776?** Check whether you run Nvidia Megatron-Bridge or Nvidia Nemo Megatron Bridge. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability involves unsafe deserialization of untrusted data in NVIDIA Megatron Bridge. An attacker can exploit this by providing specially crafted serialized payloads that, when deserialized by the application, result in arbitrary code execution. The attack requires the ability to influence or control serialized data fed to the deserialization process, which may occur through network-accessible APIs, model loading, or inter-process communication. A successful exploit enables remote code execution, data tampering, and information disclosure. Patches are expected from NVIDIA.

## Affected products

- NVIDIA Megatron Bridge

## Timeline

- 2026-09-01: disclosed

## References

- [https://github.com/NVIDIA/product-security/tree/main/2026/5868](https://github.com/NVIDIA/product-security/tree/main/2026/5868)
- [https://www.cve.org/CVERecord?id=CVE-2026-61776](https://www.cve.org/CVERecord?id=CVE-2026-61776)

## Related threats

- [NVIDIA Megatron Bridge deserialization vulnerability](https://junglewise.ai/threats/cve-2026-61779-nvidia-megatron-bridge-deserialization-vulnerability)
- [NVIDIA Megatron Bridge deserialization of untrusted data](https://junglewise.ai/threats/cve-2026-61778-nvidia-megatron-bridge-deserialization-of-untrusted-data)
- [NVIDIA Megatron Bridge unsafe deserialization](https://junglewise.ai/threats/cve-2026-61777-nvidia-megatron-bridge-unsafe-deserialization)
- [NVIDIA Megatron Bridge unsafe deserialization](https://junglewise.ai/threats/cve-2026-61775-nvidia-megatron-bridge-unsafe-deserialization)
- [NVIDIA Megatron Bridge unsafe deserialization](https://junglewise.ai/threats/cve-2026-61774-nvidia-megatron-bridge-unsafe-deserialization)