CVE-2026-49991

Severity CVSS v4.0:

Pending analysis

Type:

CWE-22 Path Traversal

Publication date:

26/06/2026

Last modified:

29/06/2026

Description

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&#39; 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.

Impact

Vector 3.x

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N CVSS v3.1 Severity and Metrics:

Base Score: 8.60 HIGH
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N

Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope (S): Changed
Confidentiality (C): None
Integrity (I): High
Availability (A): None

Base Score 3.x

8.60

Severity 3.x

HIGH

CVE-2026-49991

Description

Impact

References to Advisories, Solutions, and Tools