fix: upgrade solc 0.8.30 → 0.8.34 to mitigate TSTORE Poison compiler bug#14
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solc 0.8.28–0.8.33 with via-IR has a cache key collision in storageSetToZeroFunction: `delete` on a transient state variable can silently emit sstore instead of tstore (or vice versa), causing permanent storage corruption (e.g. zeroing owner slot, bypassing reentrancy guards, persisting stale approvals). This project meets 3 of 4 trigger conditions: - solc 0.8.30 ✓ - viaIR = true ✓ - `bool transient _locked` in 5 contracts ✓ - `delete` on transient vars ✗ (only assignment used — safe for now) While not currently exploitable (no `delete` on transient vars), upgrading to 0.8.34 eliminates the risk entirely and prevents future code changes from accidentally activating the bug. References: - https://hexens.io/research/solidity-compiler-bug-tstore-poison - https://soliditylang.org/blog/2026/02/18/transient-storage-clearing-helper-collision-bug/ Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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solc 0.8.28–0.8.33 with via-IR has a cache key collision in storageSetToZeroFunction:
deleteon a transient state variable can silently emit sstore instead of tstore (or vice versa), causing permanent storage corruption (e.g. zeroing owner slot, bypassing reentrancy guards, persisting stale approvals).This project meets 3 of 4 trigger conditions:
bool transient _lockedin 5 contracts ✓deleteon transient vars ✗ (only assignment used — safe for now)While not currently exploitable (no
deleteon transient vars), upgrading to 0.8.34 eliminates the risk entirely and prevents future code changes from accidentally activating the bug.References: