vulnerability / NVI-00017708 / Revision 1
Sync-in Server: SSRF protection bypass via IPv4-mapped IPv6 addresses in regExpPrivateIP
GitHub lists this reviewed advisory for @sync-in/server. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.
This report has not inspected your inventory, configuration, deployed build, reachability or evidence. A catalog listing and a severity score do not establish exposure or compromise.
01 / Meaning
Why it matters
Published affected context helps an owner decide what evidence to gather. This report has not examined your application.
7.7 high
GitHub source severity; exploitability and local consequence require separate evidence.
As of · GitHub Advisory Database
02 / Applicability
The affected context
Affected versions, configuration prerequisites and known exclusions are public. Confirm each one against the deployed service.
@sync-in/server
source listed<= 2.2.1
Summary: 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. Affected components backend/src/applications/files/services/files-manager.service.ts – downloadFromUrl() checks regExpPrivateIP against request.socket.remoteAddress. backend/src/applications/files/utils/url-file.ts – regExpPrivateIP does not include ::ffff: variants. Details: The regExpPrivateIP regex in backend/src/applications/files/utils/url-file.ts correctly blocks standard IPv4 private ranges but does not include ::ffff: prefixed variants. On dual-stack systems, Node.js can report a socket's remoteAddress in IPv4-mapped IPv6 form, meaning the check in FilesManager.downloadFromUrl() can be bypassed entirely. PoC: poc.pdf Proof: Impact: An attacker can supply a crafted URL pointing to an internal address that gets reported as ::ffff:127.0.0.1 or ::ffff:10.x.x.x, cau
03 / Response
What to do next
- investigate
Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.
Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database
A fixed release is not deployment evidence.
Check current vendor support and compatibility. After making a change, verify the deployed build and relevant runtime conditions. Keep the evidence, owner and time. An updated lockfile alone does not prove what is running.
04 / Limits
What this report cannot establish
- Customer inventory, deployment, reachability and exploitation have not been inspected.
05 / Provenance
Sources you can inspect
Each assertion retains its source. Mirrored records may repeat one underlying publisher; additional links are not independent corroboration.
- GHSA-q4x5-8cj6-52wg ↗
GitHub Advisory Database · vendor advisory
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Public revision history
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- Revision 1 ·
First indexed by Null; source disclosure date is shown separately.