CVE-2026-70463

rsync 3.1.0 before 3.5.0 contains an authorization bypass in auth users directive parsing. The auth users parser uses comma-only tokenization when splitting the user list, which fails to correctly handle entries of the form @Group Name where the group name contains a space. The space within the group name causes the parser to split the entry at the space boundary, discarding the deny rule associated with the group. An authenticated user whose username or group membership would be denied by an @Group Name auth users entry can connect to a restricted module because the deny rule is silently discarded during parsing.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/RsyncProject/rsync/releases/tag/v3.5.0	Product Release Notes
https://github.com/RsyncProject/rsync/security/advisories/GHSA-pfj8-79vq-xgvr	Vendor Advisory
https://www.vulncheck.com/advisories/rsync-authorization-bypass-via-auth-users-directive-parsing	Release Notes Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:samba:rsync:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-08-13 15:20

Updated : 2026-08-31 15:10

NVD link : CVE-2026-70463

Mitre link : CVE-2026-70463

CVE.ORG link : CVE-2026-70463

JSON object : View

Products Affected

samba

rsync

CWE

CWE-863

Incorrect Authorization

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