Block IPv4-compatible IPv6 addresses in SSRF protection #2273
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The SSRF filter checked ipv4_mapped? but not ipv4_compat?, allowing addresses like ::169.254.169.254 to bypass the link-local check and reach cloud metadata endpoints. Changes: - Add ipv4_compat? check to block deprecated IPv4-compatible format - Rename private_address? to blocked_address? (more accurate - method blocks more than just RFC 1918 private ranges) - Add IPv6 test coverage for both mapped and compat formats Both ipv4_mapped and ipv4_compat formats are blocked entirely as defense-in-depth: DNS never returns these formats, so they only appear in attack scenarios. HackerOne: #3481701
jayohms
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* main: (63 commits) Ignore hotkeys with modifiers Fix 1Password account ID (was user UUID) (#2278) Switch 1Password account to 37signals.1password.com (#2276) Remove CSS testing comments Max card count equals geared pagination size Block IPv4-compatible IPv6 addresses in SSRF protection (#2273) Only enable transitions on user interaction Don't update counter if value hasn't changed Add padding to upgrade message on larger screens Add test coverage for autolinking multiple URLs Add "noopener" to autolinks' rel attribute Avoid string manipulation when autolinking. Only bump z-index when nav is open Move nav and related elements above footer Delete Dockerfile.dev fix: use the right gh-cli arch package (#2232) Bump actions/attest-build-provenance from 3.0.0 to 3.1.0 (#2257) Bump docker/setup-buildx-action from 3.11.1 to 3.12.0 (#2256) Consider user avatars always public Implement authorization for Active Storage endpoints ...
andyra
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* main: Update Rails Ignore hotkeys with modifiers Fix 1Password account ID (was user UUID) (#2278) Switch 1Password account to 37signals.1password.com (#2276) Remove CSS testing comments Max card count equals geared pagination size Block IPv4-compatible IPv6 addresses in SSRF protection (#2273) Only enable transitions on user interaction Don't update counter if value hasn't changed
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The SSRF filter checked ipv4_mapped? but not ipv4_compat?, allowing addresses like ::169.254.169.254 to bypass the link-local check and reach cloud metadata endpoints.
Changes:
Both ipv4_mapped and ipv4_compat formats are blocked entirely as defense-in-depth: DNS never returns these formats, so they only appear in attack scenarios.
HackerOne: #3481701