# CVE-2025-2999: PyTorch memory corruption in unpack_sequence and pad_packed_sequence

Source: https://junglewise.ai/threats/cve-2025-2999-pytorch-memory-corruption-in-unpack-sequence-and-pad-packed  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2025-03-31. Updated: 2026-06-10  
License: CC BY 4.0 with a link back

CVE-2025-2999 · Severity: medium · CVSS 5.3 · Published 2025-03-31

PyTorch, a popular machine learning library, is vulnerable to a memory corruption issue when processing certain data sequences. An attacker with local access to a system could exploit this flaw to cause the application to crash or potentially execute unauthorized code. This could lead to service disruptions or unauthorized access to sensitive data handled by the machine learning model.

Technologies: [torch (PyPI)](https://junglewise.ai/threats/technologies/torch), [PyTorch](https://junglewise.ai/threats/technologies/pytorch). Vendors: [PyPI](https://junglewise.ai/threats/vendors/pypi), [PyTorch](https://junglewise.ai/threats/vendors/pytorch).

## Quick answers

**Is CVE-2025-2999 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2025-2999 being exploited in the wild.

**How severe is CVE-2025-2999?** Medium severity, with a CVSS score of 5.3, published 31 March 2025.

**Which products and versions are affected?** torch (PyPI) < 2.9.1, ECOSYSTEM:introduced=0,fixed=2.9.1, ECOSYSTEM:introduced=0,last_affected=2.6.0-NA; PyTorch < 2.9.1.

**Is there a fix for CVE-2025-2999?** Yes. torch (PyPI): upgrade to 2.9.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2025-2999 attacked?** It is attacked with local access, in a software library.

**Am I affected by CVE-2025-2999?** Check whether you run torch (PyPI) or PyTorch at an affected version. 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.

## How to fix

- torch (PyPI): upgrade to 2.9.1 or later

  ```sh
  pip install "torch>=2.9.1"
  ```


## Technical details

A memory corruption vulnerability (CWE-119) exists in PyTorch's RNN utility functions, specifically torch.nn.utils.rnn.unpack_sequence and torch.nn.utils.rnn.pad_packed_sequence. The issue is triggered when these functions attempt to process a PackedSequence object containing empty data or empty batch sizes, leading to a segmentation fault. A local attacker can exploit this by providing specially crafted input to an application using these functions, potentially achieving arbitrary code execution or causing a denial of service. The vulnerability was addressed in version 2.9.1 by improving error checking for empty tensors.

## Affected products

- PyTorch PyTorch < 2.9.1

## Identifiers

- CVE-2025-2999
- GHSA-vgrw-7cvw-pwgx
- PYSEC-2025-193

## Timeline

- 2025-03-20: disclosed: Issue reported on GitHub
- 2025-03-31: advisory: CVE-2025-2999 published
- 2025-03-31: patched: Patch commit 4945180 released

## References

- [https://github.com/pytorch/pytorch/issues/149622](https://github.com/pytorch/pytorch/issues/149622)
- [https://github.com/pytorch/pytorch/issues/149622](https://github.com/pytorch/pytorch/issues/149622)
- [https://vuldb.com/?ctiid.302048](https://vuldb.com/?ctiid.302048)
- [https://vuldb.com/?id.302048](https://vuldb.com/?id.302048)
- [https://vuldb.com/?submit.524198](https://vuldb.com/?submit.524198)

## Related threats

- [PYSEC-2026-1970 - PyTorch Improper Resource Shutdown or Release vulnerability](https://junglewise.ai/threats/cve-2025-3730-pytorch-improper-resource-shutdown-or-release-vulnerability)
- [PYSEC-2026-139 - A vulnerability was identified in PyTorch 2.10.0. The affected element is an unknown function of the…](https://junglewise.ai/threats/cve-2026-4538-pysec-2026-139-a-vulnerability-was-identified-in-pytorch-2-10-0)
- [PyTorch arbitrary code execution in weights_only unpickler](https://junglewise.ai/threats/cve-2026-24747-pytorch-arbitrary-code-execution-in-weights-only-unpickler)
- [PyTorch denial of service in torch.profiler.profile](https://junglewise.ai/threats/cve-2025-63396-pytorch-denial-of-service-in-torch-profiler-profile)
- [PYSEC-2025-209 - An issue in pytorch v2.7.0 can lead to a Denial of Service (DoS) when a PyTorch model consists of torch.Tensor.to_sparse() and torch.Tensor.](https://junglewise.ai/threats/cve-2025-55560-pysec-2025-209-an-issue-in-pytorch-v2-7-0-can-lead-to-a-denial-of)