CVE-2026-49991 | RustFS is a distributed object storage system built in Rust.… | CVSS 8.6 HIGH

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' 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.

Metadata

CVE ID: CVE-2026-49991
State: PUBLISHED
Assigner: GitHub_M
Reserved: 2026-06-02 18:30 UTC
Published: 2026-06-26 20:01 UTC
Last updated: 2026-06-26 20:01 UTC
Primary CWE: CWE-22
CWE-22: Improper Limitation of a Pathname to a Restricted Di…
Vendor / Product: rustfs / rustfs
Sources: cve.org · NVD

Severity & Metrics

8.6 HIGH CVSS 3.1

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

Affected products (1)

Vendor	Product	Platform	Versions
rustfs	rustfs	—	1.0.0-beta.4

Weakness (CWE)

CWE	Source	Description
CWE-22	cna	CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
CWE-862	cna	CWE-862: Missing Authorization

CVSS scores (1)

Score	Severity	Version	Source	Vector
8.6	HIGH	3.1	cna	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N

References (1)

https://github.com/rustfs/rustfs/security/advisories/GHSA-f4vq-9ffr-m8m3 https://github.com/rustfs/rustfs/security/advisories/GHSA-f4vq-9ffr-m8m3