python · pydantic-ai-slimHeads-up
pydantic-ai-slim SSRF bypass via IPv6 transition forms
SSRF protection for cloud metadata endpoints did not decode IPv6 transition forms (IPv4-compatible IPv6, NAT64 prefixes, ISATAP, Teredo), allowing bypass of the
What changed
SSRF protection for cloud metadata endpoints did not decode IPv6 transition forms (IPv4-compatible IPv6, NAT64 prefixes, ISATAP, Teredo), allowing bypass of the metadata blocklist when force_download='allow-local' is used on networks that route these forms.
Who it affects
Applications using pydantic-ai or pydantic-ai-slim >=1.56.0, <1.102.0 or >=2.0.0b1, <2.0.0b3 that set force_download='allow-local' on a FileUrl from untrusted input, on a NAT64 or ISATAP network.
What to do today
Upgrade to pydantic-ai-slim 1.102.0 or later (or 2.0.0b3 or later on the 2.0 pre-release line).
The trail
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