CVE-2026-55758

CC: Tweaked: Incomplete fix for GHSA-5jh9-2h63-pw4q: RFC 8215 NAT64 prefix (64:ff9b:1::/96) bypasses SSRF protection

MEDIUM
6.9
CVSS Score
Published: August 27, 2026 at 05:11 PM UTC
Updated: September 9, 2026 at 09:27 PM UTC
1 product affected across 1 vendorCC-Tweaked

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Severity
MEDIUM6.9
Exploit prediction
EPSS 0.5%
SSVC
PoC

Description

CC: Tweaked is a mod for Minecraft which adds programmable computers, turtles, and more to the game. Prior to 1.120.0, the SSRF protection in projects/core/src/main/java/dan200/computercraft/core/apis/http/options/AddressPredicate.java blocks the RFC 6052 64:ff9b::/96 NAT64 prefix but omits the RFC 8215 64:ff9b:1::/48 local-use prefix. On a dual-stack server using RFC 8215 NAT64, an unauthenticated user who can execute Lua code can use http.request or http.websocket with an address under 64:ff9b:1::/48 to reach loopback, RFC 1918, cloud metadata, or internal API endpoints because PrivatePattern.matches() does not classify the mapped IPv6 address as private. This issue is fixed in version 1.120.0.

Affected

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

v < 1.120.0
Affected range stops below 1.120.0, 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

6.9MEDIUMGitHub_M
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-918

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