{"id":"CVE-2020-15254","aliases":["GHSA-v5m7-53cv-f3hx","CVE-2020-35904","GHSA-m8h8-v6jh-c762","RUSTSEC-2020-0052"],"title":"crossbeam-channel Undefined Behavior before v0.4.4","summary":"crossbeam-channel Undefined Behavior before v0.4.4","severity":"high","cvss":8.1,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","vendor":"crossbeam-channel","product":"crossbeam-channel","ecosystem":"rust","affected":["crossbeam-channel >= 0.4.3, < 0.4.4"],"patched":["crossbeam-channel 0.4.4"],"published":"2021-08-25","updated":"2026-07-08","source":"OSV","sourceUrl":"https://osv.dev/vulnerability/GHSA-v5m7-53cv-f3hx","references":[{"url":"https://github.com/crossbeam-rs/crossbeam/security/advisories/GHSA-v5m7-53cv-f3hx"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2020-15254"},{"url":"https://github.com/crossbeam-rs/crossbeam/issues/539"},{"url":"https://github.com/RustSec/advisory-db/pull/425"},{"url":"https://github.com/crossbeam-rs/crossbeam/pull/533"},{"url":"https://github.com/crossbeam-rs/crossbeam"},{"url":"https://rustsec.org/advisories/RUSTSEC-2020-0052.html"}],"tags":["osv","rust"],"epss":0.02701,"epssPercentile":0.85306,"ingestedAt":"2026-07-09T18:56:37.329Z","slug":"CVE-2020-15254","body":"## Overview\n\n### Impact\n\nThe affected version of this crate's the `bounded` channel incorrectly assumes that `Vec::from_iter` has allocated capacity that same as the number of iterator elements. `Vec::from_iter` does not actually guarantee that and may allocate extra memory. The destructor of the `bounded` channel reconstructs `Vec` from the raw pointer based on the incorrect assumes described above. This is unsound and causing deallocation with the incorrect capacity when `Vec::from_iter` has allocated different sizes with the number of iterator elements.\n\n### Patches\n\nThis has been fixed in crossbeam-channel 0.4.4.\n\nWe recommend users to upgrade to 0.4.4.\n\n### References\n\nSee https://github.com/crossbeam-rs/crossbeam/pull/533, https://github.com/crossbeam-rs/crossbeam/issues/539, and https://github.com/RustSec/advisory-db/pull/425 for more details.\n\n### License\n\nThis advisory is in the public domain.\n\n## Affected packages\n\n- `crossbeam-channel >= 0.4.3, < 0.4.4`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `crossbeam-channel 0.4.4`","depth":"twilight","depthScore":45,"depthScoreParts":{"impact":44.6,"likelihood":0.5,"exploitation":0,"ransomware":0},"changes":[]}