CVE-2026-47684

Sync-in Server: SSRF protection bypass via IPv4-mapped IPv6 addresses in regExpPrivateIP

HIGH
7.7
CVSS Score
Published: June 16, 2026 at 02:31 PM UTC
Updated: October 25, 2026 at 11:10 PM UTC
1 product affected across 1 vendorSync-in Server

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Severity
HIGH7.7
Exploit prediction
EPSS 0.2%
SSVC
PoC

Description

Sync-in Server is a secure, open-source platform for file storage, sharing, collaboration, and syncing. Prior to version 2.3.0, the private IP blocklist regex used in the URL download feature does not match IPv4-mapped IPv6 addresses (e.g. ::ffff:127.0.0.1), allowing SSRF protection to be bypassed on dual-stack systems. Version 2.3.0 fixes the issue.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 2.3.0
Affected range stops below 2.3.0, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

SSVC — Action Prioritization

SSVCPoCNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.7HIGHGitHub_M
Attack Vector
NETWORK
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
CHANGED
Confidentiality
HIGH
Integrity
NONE
Availability
NONE
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-918

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