---
id: CVE-2026-5559
aliases:
  - GHSA-23jg-5f8m-gw8c
  - PYSEC-2026-2975
title: 'PyBlade: SSTI/RCE via Bypassed AST Validation in sandbox.py'
summary: 'PyBlade: SSTI/RCE via Bypassed AST Validation in sandbox.py'
severity: medium
cvss: 6.3
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L'
vendor: pyblade
product: pyblade
ecosystem: pip
affected:
  - 'pyblade >= 0.1.8-alpha, <= 0.2.0-alpha'
published: '2026-04-05'
updated: '2026-07-13'
source: OSV
sourceUrl: 'https://osv.dev/vulnerability/GHSA-23jg-5f8m-gw8c'
references:
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-5559'
  - url: 'https://github.com/AntaresMugisho/PyBlade/issues/1'
  - url: 'https://github.com/AntaresMugisho/PyBlade/issues/1#issue-4086730906'
  - url: 'https://github.com/AntaresMugisho/PyBlade'
  - url: 'https://vuldb.com/submit/782904'
  - url: 'https://vuldb.com/vuln/355329'
  - url: 'https://vuldb.com/vuln/355329/cti'
tags:
  - osv
  - pip
epss: 0.00413
epssPercentile: 0.3295
ingestedAt: '2026-07-13T18:57:51.013Z'
---

## Overview

A vulnerability has been found in AntaresMugisho PyBlade 0.1.8-alpha/0.1.9-alpha. The affected element is the function _is_safe_ast of the file sandbox.py of the component AST Validation. Such manipulation leads to improper neutralization of special elements used in a template engine. The attack may be performed from remote. The exploit has been disclosed to the public and may be used. The project was informed of the problem early through an issue report but has not responded yet.

## Affected packages

- `pyblade >= 0.1.8-alpha, <= 0.2.0-alpha`

## Remediation

Refer to the advisory for the patched release.