CVE-2026-49991 HIGH

CVE-2026-49991: RustFS Snowball Auto-Extract: Path Traversal allows cross-bucket object injection

Vendor Rustfs
Product rustfs
Weakness CWE-22 · Path traversal
Published June 26, 2026
Last update June 29, 2026
View on NVD All CVEs

CVSS base score

8.6/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality None
Integrity High

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N

What the vulnerability does

01Description

RustFS is a distributed object storage system built in Rust. In 1.0.0-beta.4, authenticated users with only PutObject permission on their own bucket can exploit a path traversal vulnerability in the Snowball auto-extract feature to write arbitrary objects into other users' buckets, completely breaking multi-tenant isolation. The vulnerability chains three flaws: No ../ sanitization in tar entry key normalization; IAM wildcard matching uses raw (uncleaned) paths; and Filesystem path cleaning resolves ../ across bucket boundaries.

Key dates

02Disclosure timeline

June 26, 2026 CVE published
June 29, 2026 Record updated