{"id":"CVE-2020-35907","aliases":["EUVD-2022-4723","GHSA-p9m5-3hj7-cp5r","RUSTSEC-2020-0061","UBUNTU-CVE-2020-35907"],"status":"published","title":"futures_task::noop_waker_ref can segfault due to dereferencing a NULL pointer","description":"An issue was discovered in the futures-task crate before 0.3.5 for Rust. futures_task::noop_waker_ref allows a NULL pointer dereference.","severity":{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-09","score":0.00407,"percentile":0.35289,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-476"],"published":"2020-05-03T12:00:00Z","modified":"2026-10-24T10:31:00Z","fixes":[{"ecosystem":"crates.io","package":"futures-task","fixed_in":["0.3.5"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"crates.io","package":"futures-task","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.3.5"}]}]},{"source":"osv","ecosystem":"crates.io","package":"futures-task","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"0.3.5"}]}]},{"source":"osv","ecosystem":"crates.io","package":"futures-task","ranges":[{"type":"SEMVER","events":[{"introduced":"0.0.0-0"},{"fixed":"0.3.5"}]}]},{"source":"osv","ecosystem":"Ubuntu:22.04:LTS","package":"rust-futures-task","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.3.8-1","0.3.17-1"]},{"source":"osv","ecosystem":"Ubuntu:24.04:LTS","package":"rust-futures-task","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.3.28-1","0.3.29-1","0.3.30-1"]},{"source":"osv","ecosystem":"Ubuntu:25.10","package":"rust-futures-task","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.3.31-3"]},{"source":"osv","ecosystem":"Ubuntu:26.10","package":"rust-futures-task","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.3.31-3","0.3.32-1","0.3.33-1"]},{"source":"osv","ecosystem":"Ubuntu:26.04:LTS","package":"rust-futures-task","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.3.31-3"]}],"products":[{"vendor":"rust-lang","product":"futures-task"}],"references":[{"url":"https://rustsec.org/advisories/RUSTSEC-2020-0061.html","tags":["x_refsource_MISC","x_transferred","Exploit","Third Party Advisory","evidence","web","advisory","report"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2020-35907","tags":["advisory"]},{"url":"https://github.com/rust-lang/futures-rs/issues/2091","tags":["web","report"]},{"url":"https://github.com/advisories/GHSA-p9m5-3hj7-cp5r"},{"url":"https://github.com/rust-lang/futures-rs","tags":["package"]},{"url":"https://crates.io/crates/futures-task","tags":["package"]},{"url":"https://ubuntu.com/security/CVE-2020-35907","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2020-35907","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2020-35907","description":"An issue was discovered in the futures-task crate before 0.3.5 for Rust. futures_task::noop_waker_ref allows a NULL pointer dereference.","status":"published","published":"2020-12-31T08:20:58Z","modified":"2024-08-04T17:16:13.217Z","updated_at":"2026-11-02T14:35:57.975444Z"}],"euvd":[{"id":"EUVD-2022-4723","description":"An issue was discovered in the futures-task crate before 0.3.5 for Rust. futures_task::noop_waker_ref allows a NULL pointer dereference.","status":"published","published":"2020-12-31T08:20:58Z","modified":"2024-08-04T17:16:13Z","updated_at":"2026-11-03T03:07:04.065361Z"}],"ghsa":[{"id":"GHSA-p9m5-3hj7-cp5r","title":"futures_task::noop_waker_ref can segfault due to dereferencing a NULL pointer","description":"Affected versions of the crate used a UnsafeCell in thread-local storage to return a noop waker reference, assuming that the reference would never be returned from another thread.\n\nThis resulted in a segmentation fault crash if Waker::wake_by_ref() was called on a waker returned from another thread due to it attempting to dereference a pointer that wasn't accessible from the main thread.","status":"published","published":"2022-05-24T17:37:49Z","modified":"2023-06-13T17:24:57Z","cvss":[{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium"}],"cwes":["CWE-476"],"updated_at":"2026-11-02T14:36:53.654352Z"}],"nvd":[{"id":"CVE-2020-35907","description":"An issue was discovered in the futures-task crate before 0.3.5 for Rust. futures_task::noop_waker_ref allows a NULL pointer dereference.","status":"published","published":"2020-12-31T09:15:15.24Z","modified":"2026-06-17T03:14:34.867Z","cvss":[{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"primary"},{"version":"2.0","score":2.1,"vector":"AV:L/AC:L/Au:N/C:N/I:N/A:P","level":"low","assessor":"primary"}],"cwes":["CWE-476"],"updated_at":"2026-11-02T14:06:28.340168Z"}],"osv":[{"id":"CVE-2020-35907","description":"An issue was discovered in the futures-task crate before 0.3.5 for Rust. futures_task::noop_waker_ref allows a NULL pointer dereference.","status":"published","published":"2020-12-31T09:15:15.24Z","modified":"2026-10-24T10:31:00.840451502Z","cvss":[{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium"}],"updated_at":"2026-11-02T15:44:16.612899Z"},{"id":"GHSA-p9m5-3hj7-cp5r","title":"futures_task::noop_waker_ref can segfault due to dereferencing a NULL pointer","description":"Affected versions of the crate used a UnsafeCell in thread-local storage to return a noop waker reference, assuming that the reference would never be returned from another thread.\n\nThis resulted in a segmentation fault crash if Waker::wake_by_ref() was called on a waker returned from another thread due to it attempting to dereference a pointer that wasn't accessible from the main thread.","status":"published","published":"2022-05-24T17:37:49Z","modified":"2023-11-08T04:03:38.673466Z","cvss":[{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium"}],"cwes":["CWE-476"],"updated_at":"2026-11-02T15:46:52.891208Z"},{"id":"RUSTSEC-2020-0061","title":"futures_task::noop_waker_ref can segfault due to dereferencing a NULL pointer","description":"Affected versions of the crate used a `UnsafeCell` in thread-local storage to return a noop waker reference,\nassuming that the reference would never be returned from another thread.\n\nThis resulted in a segmentation fault crash if `Waker::wake_by_ref()` was called on a waker returned from another thread due to \nit attempting to dereference a pointer that wasn't accessible from the main thread.\n\nReproduction Example (from issue):\n```rust\nuse futures_task::noop_waker_ref;\nfn main() {\n    let waker = std::thread::spawn(|| noop_waker_ref()).join().unwrap();\n    waker.wake_by_ref();\n}\n```\n\nThe flaw was corrected by using a `OnceCell::Lazy\u003c\u003e` wrapper around the noop waker instead of thread-local storage.","status":"published","published":"2020-05-03T12:00:00Z","modified":"2023-11-08T04:03:38.673466Z","cvss":[{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium"}],"updated_at":"2026-11-02T15:53:39.492624Z"},{"id":"UBUNTU-CVE-2020-35907","description":"An issue was discovered in the futures-task crate before 0.3.5 for Rust. futures_task::noop_waker_ref allows a NULL pointer dereference.","status":"published","published":"2020-12-31T09:15:00Z","modified":"2026-10-17T12:56:13.889334245Z","cvss":[{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium"}],"updated_at":"2026-11-02T15:54:25.179924Z"}]}}