Description
A vulnerability, which was classified as problematic, was found in PyTorch 2.6.0. Affected is the function torch.nn.functional.ctc_loss of the file aten/src/ATen/native/LossCTC.cpp. The manipulation leads to denial of service. An attack has to be approached locally. The exploit has been disclosed to the public and may be used. The real existence of this vulnerability is still doubted at the moment. The name of the patch is 46fc5d8e360127361211cb237d5f9eef0223e567. It is recommended to apply a patch to fix this issue. The security policy of the project warns to use unknown models which might establish malicious effects.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| — | PyTorch | 2.6.0 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | pytorch | 2.12.0+dfsg2-1 | — |
| Debian 13 | pytorch | No fix yet | — |
| Debian 12 | pytorch | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | pytorch | No fix yet | — |
| Ubuntu 26.04 LTS | pytorch | No fix yet | — |
| Ubuntu 25.10 | pytorch | No fix yet | — |
| Ubuntu 22.04 LTS | pytorch | No fix yet | — |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | pytorch | 2.2.2-6 | — |
| Azure Linux 2 (CBL-Mariner) | pytorch | 2.0.0-8 | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| PyPI | torch | < 2.8.0 | 2.8.0 | GHSA-887c-mr87-cxwp |
Advisories 1
- WID-SEC-2025-0839 PyTorch: Schwachstelle ermöglicht Denial of Service BSI CERT-Bund (WID) · Apr 16, 2025
References
- VDB-305076 | PyTorch LossCTC.cpp torch.nn.functional.ctc_loss denial of service vdb-entry technical-description
- VDB-305076 | CTI Indicators (IOB, IOC, IOA) signature permissions-required
- Submit #553645 | pytorch pytorch (in torch.nn.functional.ctc_loss) 2.6.0 Denial of Service third-party-advisory
- https://github.com/pytorch/pytorch/issues/150835 issue-tracking
- https://github.com/pytorch/pytorch/pull/150981 issue-tracking
- https://github.com/pytorch/pytorch/issues/150835#issue-2979082232 exploit issue-tracking
- https://github.com/timocafe/tewart-pytorch/commit/46fc5d8e360127361211cb237d5f9eef0223e567 patch