{"id":"RUSTSEC-2026-0300","aliases":["GHSA-x6j6-3ffp-qrfr"],"title":"Use-after-free in `clear` and `retain` when an element's `Drop` panics","summary":"Use-after-free in `clear` and `retain` when an element's `Drop` panics","severity":"none","vendor":"skiplist","product":"skiplist","ecosystem":"rust","affected":["skiplist >= 0.0.0-0, < 1.1.1"],"patched":["skiplist 1.1.1"],"published":"2026-09-02","updated":"2026-09-22","sourceUpdated":"2026-09-22T07:45:03.895629896Z","source":"OSV","sourceUrl":"https://osv.dev/vulnerability/RUSTSEC-2026-0300","references":[{"url":"https://crates.io/crates/skiplist"},{"url":"https://rustsec.org/advisories/RUSTSEC-2026-0300.html"},{"url":"https://github.com/JP-Ellis/rust-skiplist/pull/334"}],"tags":["osv","rust"],"ingestedAt":"2026-09-24T07:16:01.871Z","slug":"RUSTSEC-2026-0300","body":"## Overview\n\n`SkipList::clear` drops the node chain and only then resets `tail` and `len`.\nThe drop runs each element's `Drop`, and `T` carries no bounds excluding a\npanicking one. If it unwinds, `tail` still points at the freed node while `len`\nstays non-zero.\n\n`back()`, `back_mut()`, `last_key_value()` and `last()` dereference `tail`\nthrough `unsafe`, so reading the container after the unwind is a use-after-free\n(CWE-416). `Drop for SkipList` calls `Box::from_raw` on `self.head`, which\n`clear` already destroyed, so dropping the container is a double free\n(CWE-415).\n\n`retain`, `retain_mut` and `dedup_by` reach the same state through\n`Node::filter_rebuild`, which frees nodes and runs a user predicate before the\ncaller commits `tail` and `len`. There the head links are left partially\nrewired, so traversal can also reach freed nodes.\n\n## Mitigation\n\nUpdate to 1.1.1.\n\n## Affected packages\n\n- `skiplist >= 0.0.0-0, < 1.1.1`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `skiplist 1.1.1`","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}