fix(security): block NAT64/6to4/Teredo IPv6 addresses embedding private IPv4 in SSRF guard#995
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ital0 wants to merge 2 commits into
Open
fix(security): block NAT64/6to4/Teredo IPv6 addresses embedding private IPv4 in SSRF guard#995ital0 wants to merge 2 commits into
ital0 wants to merge 2 commits into
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…te IPv4 in SSRF guard
Semgrep Security ScanNo security issues found. |
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Updated Thu, 18 Jun 2026 21:26:48 GMT · run #1954 |
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Note
Medium Risk
Changes security-critical outbound fetch validation used by link preview; behavior is tightened with tests, but misclassification of NAT64/public embeds could break legitimate DNS64 fetches.
Overview
Extends
isPrivateAddressinurl-validation.tswithembeddedIpv4, so IPv6 transition forms (NAT6464:ff9b::/96, 6to4, RFC6145, Teredo) are treated as private when the embedded IPv4 is internal—while still allowing NAT64/DNS64 addresses that wrap public IPv4.Adds broad SSRF regression tests: alternate IPv4 encodings, bracketed IPv6 literals, userinfo decoys, DNS rebinding and NAT64 AAAA cases for
validateAndPin/createSafeFetch, plusPOST /v1/previewe2e checks that the advisory path-style route is absent and loopback/rebind targets are blocked without caching leaked metadata.Reviewed by Cursor Bugbot for commit 9c6e480. Bugbot is set up for automated code reviews on this repo. Configure here.