CVE-2026-3219: PyPA pip interpretation conflict in concatenated archive handling

CVE-2026-3219 · Severity: medium · CVSS 4 · Published 2026-04-20

A vulnerability in the Python package manager (pip) allows for an interpretation conflict when handling specially crafted archive files. An attacker could create a file that appears to be one type of archive (like a .tar file) but is processed as another (like a .zip file), potentially leading to the installation of unintended or malicious code. This could compromise the integrity of software environments and automated deployment pipelines.

Technologies: pip (PyPI). Vendors: PyPI.

Quick answers

Is CVE-2026-3219 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-3219 being exploited in the wild.
How severe is CVE-2026-3219?
Medium severity, with a CVSS score of 4, published 20 April 2026.
Which products and versions are affected?
pip (PyPI) <= 26.0.1, ECOSYSTEM:introduced=0,fixed=26.1.
Is there a fix for CVE-2026-3219?
Yes. pip (PyPI): upgrade to 26.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-3219 attacked?
It is attacked with local access, in a software library.
Am I affected by CVE-2026-3219?
Check whether you run pip (PyPI) 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

  • pip (PyPI): upgrade to 26.1 or later
    pip install "pip>=26.1"

Technical details

pip versions up to 26.0.1 are vulnerable to an interpretation conflict (polyglot file attack) where concatenated tar and ZIP files are processed exclusively as ZIP files. This occurs regardless of the file extension or the presence of tar headers. An attacker can exploit this by providing a malicious archive that pip misinterprets, leading to the installation of files that do not match the intended archive content. The fix, introduced in version 26.1, ensures that pip only proceeds with installation if the file identifies uniquely as either a ZIP or a tar archive, but not both. Exploitation requires local access and user interaction to initiate the installation of the crafted file.

Affected products

  • PyPA pip <= 26.0.1

Identifiers

  • CVE-2026-3219
  • GHSA-58qw-9mgm-455v
  • PYSEC-2026-2875

Timeline

  • 2026-04-20: disclosed
  • 2026-04-20: advisory
  • 2026-04-20: patched: Fixed in version 26.1

References

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