CVE-2026-3087 PUBLISHED

shutil.unpack_archive() doesn't check for Windows absolute paths in ZIPs

Assigner: PSF
Reserved: 23.02.2026 Published: 27.04.2026 Updated: 28.04.2026

If shutil.unpack_archive() is given a ZIP archive with an absolute Windows path containing a drive (C:\\...) then the archive will be extracted outside the target directory which is different than other operating systems. Only Windows is affected by this vulnerability.

Metrics

CVSS 4.0

CVSS Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
CVSS Score: 6

Exploitability Metrics		Vulnerable System Impact Metrics		Subsequent System Impact Metrics
Attack Vector	Network	Confidentiality	None	Confidentiality	None
Attack Complexity	Low	Integrity	High	Integrity	None
Attack Requirements	Present	Availability	None	Availability	None
Privileges Required	Low
User Interaction	None

CVSS 4.0

Product Status

Vendor	Python Software Foundation
Product	CPython
Versions	Default: unaffected Version 0 is affected

Credits

Serhiy Storchaka (https://github.com/serhiy-storchaka) remediation developer
Seth Larson (https://github.com/sethmlarson) coordinator
GGAutomaton (https://github.com/GGAutomaton) reporter

References

Problem Types

CWE-22 CWE