{"id":"RUSTSEC-2026-0253","title":"Potential use-after-free due to lack of panic safety in `LruCache::pop()`","summary":"Potential use-after-free due to lack of panic safety in `LruCache::pop()`","severity":"none","vendor":"lru","product":"lru","ecosystem":"rust","affected":["lru >= 0.0.0-0, < 0.18.2"],"patched":["lru 0.18.2"],"published":"2026-05-12","updated":"2026-08-11","source":"OSV","sourceUrl":"https://osv.dev/vulnerability/RUSTSEC-2026-0253","references":[{"url":"https://crates.io/crates/lru"},{"url":"https://rustsec.org/advisories/RUSTSEC-2026-0253.html"},{"url":"https://github.com/jeromefroe/lru-rs/pull/238"}],"tags":["osv","rust"],"ingestedAt":"2026-08-11T19:17:10.484Z","slug":"RUSTSEC-2026-0253","body":"## Overview\n\n`LruCache::pop()` in `lru` was not panic-safe. If the `Drop` implementation of a stored key panics during `pop()`, `self.detach()` is never called, leaving dangling pointers in the internal doubly-linked list.\n\nA subsequent cache operation that triggers eviction can then dereference these dangling pointers:\n- The node is freed from the map, but remains linked in the LRU list due to the skipped `detach()` call\n- When a new insertion causes eviction, the LRU traversal encounters the dangling pointer\n- This results in a write to already-freed memory during the eviction process\n\n## Impact\n\n- **CWE-416 (Use-After-Free):** memory corruption when subsequent cache operations access freed node pointers in the linked list\n- **CWE-415 (Double Free):** potential heap corruption when the same memory is freed multiple times\n\nBoth types of undefined behavior can be invoked in safe Rust, but only if unwinding panics are enabled and `std::panic::catch_unwind` is used with key types that have potentially-panicking `Drop` implementations.\n\n## Fix\n\nFixed in `lru` 0.18.2 by detaching the node from the linked list before freeing it and dropping the key ([lru-rs#238](https://github.com/jeromefroe/lru-rs/pull/238)).\n\n## Affected packages\n\n- `lru >= 0.0.0-0, < 0.18.2`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `lru 0.18.2`","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}