Improper Handling of Highly Compressed Data (Data Amplification) Affecting py7zr package, versions [,1.1.3)
Threat Intelligence
Snyk has a proof-of-concept or detailed explanation of how to exploit this vulnerability.
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-PYTHON-PY7ZR-17391450
- published21 Jun 2026
- disclosed19 Jun 2026
- creditDUAC_PAUD
Introduced: 19 Jun 2026
CVE-2026-55195 (opens in a new tab)How to fix?
Upgrade py7zr to version 1.1.3 or higher.
Overview
py7zr is a Pure python 7-zip library
Affected versions of this package are vulnerable to Improper Handling of Highly Compressed Data (Data Amplification) via the decompress function. An attacker can cause resource exhaustion by providing a specially crafted archive that expands to a much larger size upon extraction.