CVE-2026-47684 json
Sync-in Server: SSRF protection bypass via IPv4-mapped IPv6 addresses in regExpPrivateIP
published 2026-06-05 5 mo ago modified 2026-10-25 14 d ago also GHSA-q4x5-8cj6-52wg , EUVD-2026-37123
- cvss
- 7.7
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 12%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- partial
- Assessed
- 4 mo ago
Exploit prediction
0.22% chance of exploitation in the next 30 days, higher than 12% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/Sync-in/server/security/advisories/GHSA-q4x5-8cj6-52wg referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.7 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N |
| GitHub | 3.1 | 7.7 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| npm | @sync-in/server | <2.3.0 |
2.3.0 |
Affected products
- Sync-in server
Classification
- Weakness
-
- CWE-918 Server-Side Request Forgery
References
Sources
- CVE List CVE-2026-47684
- GitHub Advisory GHSA-q4x5-8cj6-52wg
- NVD CVE-2026-47684
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.