Anchor: `InterfaceAccount` allows account substitution between unexpected types — GHSA-429Q-FHH4-R6HJ

Summary

### Impact Any uses of `InterfaceAccount` allows another unexpected account type to be passed, after https://github.com/solana-foundation/anchor/pull/3837 disabled discriminator checking for this type. The bug was originally reported and fixed in https://github.com/solana-foundation/anchor/pull/4139, see that PR for more details. ### Patches https://github.com/solana-foundation/anchor/pull/4139 patched the issue…

Product

rust: anchor-lang

What to do

General, cautious steps (verify details in the official source):

• Prioritize patching or mitigation immediately (treat as actively risky).
• Identify affected product versions in your inventory and verify whether you are impacted.
• Apply vendor patches/updates or recommended mitigations as soon as available.
• Read the official advisory for exact affected versions and remediation steps.

Official advisory

• Read the official source

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