CVE-2025-71437 PUBLISHED

Astral uv through 0.8.21 Path Traversal via Symlinks in Sdist Tar Extraction

Assigner: VulnCheck
Reserved: 20.10.2026 Published: 21.10.2026 Updated: 21.10.2026

Astral uv before 0.8.22 contains a path traversal vulnerability in source distribution (sdist) tar extraction that allows a specially crafted sequence of symlinks to redirect file writes outside the intended extraction prefix. Attackers can publish a malicious sdist that, when installed by a victim, writes arbitrary files to filesystem locations outside the installation prefix.

CVSS Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
CVSS Score: 8.7

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

CVSS 4.0

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
CVSS Score: 6.5

Attack Vector	Network	Scope	Unchanged
Attack Complexity	Low	Confidentiality Impact	None
Privileges Required	None	Integrity Impact	High
User Interaction	Required	Availability Impact	None

CVSS 3.1

Product Status

Vendor	astral-sh
Product	uv
Versions	Default: unaffected affected from 0 to 0.8.21 (incl.)

Credits

calebbrown finder
charliermarsh finder
woodruffw coordinator
zanieb finder

References

Problem Types

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') CWE