{"id":"CVE-2018-20996","aliases":["RUSTSEC-2018-0009","GHSA-c3cw-c387-pj65"],"title":"MsQueue and SegQueue suffer from double-free","summary":"MsQueue and SegQueue suffer from double-free","severity":"critical","cvss":9.8,"cvssVector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","vendor":"crossbeam","product":"crossbeam","ecosystem":"rust","affected":["crossbeam >= 0.4.0, < 0.4.1"],"patched":["crossbeam 0.4.1"],"published":"2018-12-09","updated":"2026-07-17","source":"OSV","sourceUrl":"https://osv.dev/vulnerability/RUSTSEC-2018-0009","references":[{"url":"https://crates.io/crates/crossbeam"},{"url":"https://rustsec.org/advisories/RUSTSEC-2018-0009.html"},{"url":"https://github.com/crossbeam-rs/crossbeam-epoch/issues/82"}],"tags":["osv","rust"],"epss":0.01598,"epssPercentile":0.74278,"ingestedAt":"2026-07-17T19:00:51.663Z","slug":"CVE-2018-20996","body":"## Overview\n\nEven if an element is popped from a queue, crossbeam would run its\ndestructor inside the epoch-based garbage collector. This is a source\nof double frees.\n\nThe flaw was corrected by wrapping elements inside queues in a\n`ManuallyDrop`.\n\nThanks to [@c0gent](https://github.com/c0gent) for reporting the issue.\n\n## Affected packages\n\n- `crossbeam >= 0.4.0, < 0.4.1`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `crossbeam 0.4.1`","depth":"midnight","depthScore":54,"depthScoreParts":{"impact":53.9,"likelihood":0.3,"exploitation":0,"ransomware":0},"changes":[]}