{"id":"CVE-2026-82743","aliases":["EEF-CVE-2026-82743","EUVD-2026-68948","GHSA-33wq-x3q2-c92h"],"status":"published","title":"Ash.Actions.Read.AsyncLimiter busy-spins a scheduler while awaiting slow async reads","description":"Uncontrolled Resource Consumption vulnerability in ash-project ash lets a slow asynchronous read spin a scheduler thread at full CPU while the framework waits for it.\n\nAsh.Actions.Read.AsyncLimiter.await_at_least_one/1 (lib/ash/actions/read/async_limiter.ex) waited for concurrent async read tasks by polling each with Task.yield(task, 0) in a tight loop rather than blocking. While every outstanding task is still running (a slow related-data load or calculation), the loop returns immediately and repeats, busy-spinning and holding a BEAM scheduler at full CPU for the whole duration of the slow read; concurrent slow reads tie up further schedulers. The fix waits with Task.yield_many (a non-blocking sweep followed by a blocking wait with timeout: :infinity), so the process sleeps until a task completes instead of spinning.\n\nThis issue affects ash: from 2.19.0 before 3.32.2.","severity":{"version":"4.0","score":2.1,"vector":"CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N","level":"low","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.0018,"percentile":0.07645,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-400"],"published":"2026-09-01T03:37:24Z","modified":"2026-10-28T02:30:32Z","fixes":[{"ecosystem":"Hex","package":"ash","fixed_in":["3.32.2"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Hex","package":"ash","ranges":[{"type":"SEMVER","events":[{"introduced":"2.19.0"},{"fixed":"3.32.2"}]}],"versions":["2.19.0","2.19.1","2.19.10","2.19.11","2.19.12","2.19.13","2.19.14","2.19.2","2.19.3","2.19.4","2.19.5","2.19.6","2.19.7","2.19.8","2.19.9","2.20.0","2.20.1","2.20.2","2.20.3","2.21.0","2.21.1","2.21.10","2.21.11","2.21.12","2.21.13","2.21.14","2.21.15","2.21.2","2.21.3","2.21.4","2.21.5","2.21.6","2.21.7","2.21.8","2.21.9","3.0.0","3.0.0-rc.0","3.0.0-rc.1","3.0.0-rc.10","3.0.0-rc.11","3.0.0-rc.12","3.0.0-rc.13","3.0.0-rc.14","3.0.0-rc.15","3.0.0-rc.16","3.0.0-rc.17","3.0.0-rc.18","3.0.0-rc.19","3.0.0-rc.20","3.0.0-rc.21","3.0.0-rc.22","3.0.0-rc.23","3.0.0-rc.24","3.0.0-rc.25","3.0.0-rc.26","3.0.0-rc.27","3.0.0-rc.28","3.0.0-rc.29","3.0.0-rc.3","3.0.0-rc.31","3.0.0-rc.32","3.0.0-rc.33","3.0.0-rc.34","3.0.0-rc.35","3.0.0-rc.36","3.0.0-rc.37","3.0.0-rc.38","3.0.0-rc.39","3.0.0-rc.4","3.0.0-rc.40","3.0.0-rc.41","3.0.0-rc.42","3.0.0-rc.43","3.0.0-rc.44","3.0.0-rc.45","3.0.0-rc.46","3.0.0-rc.5","3.0.0-rc.6","3.0.0-rc.7","3.0.0-rc.8","3.0.0-rc.9","3.0.1","3.0.10","3.0.11","3.0.12","3.0.13","3.0.14","3.0.15","3.0.16","3.0.2","3.0.3","3.0.4","3.0.5","3.0.6","3.0.7","3.0.8","3.0.9","3.1.0","3.1.1","3.1.2","3.1.3","3.1.4","3.1.5","3.1.6","3.1.7","3.1.8","3.10.0","3.10.1","3.11.0","3.11.1","3.11.2","3.11.3","3.12.0","3.13.0","3.13.1","3.13.2","3.14.0","3.14.1","3.15.0","3.16.0","3.17.0","3.17.1","3.18.0","3.19.0","3.19.1","3.19.2","3.19.3","3.2.0","3.2.1","3.2.2","3.2.3","3.2.4","3.2.5","3.2.6","3.20.0","3.21.0","3.21.1","3.21.2","3.21.3","3.22.0","3.22.1","3.22.2","3.23.0","3.23.1","3.24.0","3.24.1","3.24.2","3.24.3","3.24.4","3.24.5","3.24.6","3.24.7","3.25.0","3.25.1","3.25.2","3.26.0","3.27.0","3.27.1","3.27.2","3.27.3","3.27.4","3.27.5","3.27.6","3.27.7","3.27.8","3.28.0","3.29.0","3.29.1","3.29.2","3.29.3","3.3.0","3.3.1","3.3.2","3.3.3","3.30.0","3.30.1","3.31.0","3.31.1","3.31.2","3.31.3","3.32.0","3.32.1","3.4.0","3.4.1","3.4.10","3.4.11","3.4.12","3.4.13","3.4.14","3.4.15","3.4.16","3.4.17","3.4.18","3.4.19","3.4.2","3.4.20","3.4.21","3.4.22","3.4.23","3.4.24","3.4.25","3.4.26","3.4.27","3.4.28","3.4.29","3.4.3","3.4.30","3.4.31","3.4.32","3.4.33","3.4.34","3.4.35","3.4.36","3.4.37","3.4.38","3.4.39","3.4.4","3.4.40","3.4.41","3.4.42","3.4.43","3.4.44","3.4.45","3.4.46","3.4.47","3.4.48","3.4.49","3.4.5","3.4.50","3.4.51","3.4.52","3.4.53","3.4.54","3.4.55","3.4.56","3.4.57","3.4.58","3.4.59","3.4.6","3.4.60","3.4.61","3.4.62","3.4.63","3.4.64","3.4.65","3.4.66","3.4.67","3.4.68","3.4.69","3.4.7","3.4.70","3.4.71","3.4.72","3.4.73","3.4.74","3.4.8","3.4.9","3.5.0","3.5.1","3.5.10","3.5.11","3.5.12","3.5.13","3.5.14","3.5.15","3.5.16","3.5.17","3.5.18","3.5.19","3.5.2","3.5.20","3.5.21","3.5.22","3.5.23","3.5.24","3.5.25","3.5.26","3.5.27","3.5.28","3.5.29","3.5.3","3.5.30","3.5.31","3.5.32","3.5.33","3.5.34","3.5.35","3.5.36","3.5.37","3.5.38","3.5.39","3.5.4","3.5.40","3.5.41","3.5.42","3.5.43","3.5.5","3.5.6","3.5.7","3.5.8","3.5.9","3.6.0","3.6.1","3.6.2","3.6.3","3.7.0","3.7.1","3.7.2","3.7.3","3.7.4","3.7.5","3.7.6","3.8.0","3.9.0"]}],"products":[{"vendor":"ash-project","product":"ash"}],"references":[{"url":"https://github.com/ash-project/ash/security/advisories/GHSA-33wq-x3q2-c92h","tags":["vendor-advisory","related","exploit","advisory"]},{"url":"https://cna.erlef.org/cves/CVE-2026-82743.html","tags":["related","web"]},{"url":"https://osv.dev/vulnerability/EEF-CVE-2026-82743","tags":["related","web"]},{"url":"https://github.com/ash-project/ash/commit/0a5ecd2ffdfa848afdeb8827f02982ef2a63a1cd","tags":["patch","fix"]},{"url":"https://github.com","tags":["web"]},{"url":"https://repo.hex.pm","tags":["web"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/82xxx/CVE-2026-82743.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-82743","tags":["advisory"]},{"url":"https://github.com/ash-project/ash","tags":["package"]},{"url":"https://hex.pm/packages/ash","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2026-82743","title":"Ash.Actions.Read.AsyncLimiter busy-spins a scheduler while awaiting slow async reads","description":"Uncontrolled Resource Consumption vulnerability in ash-project ash lets a slow asynchronous read spin a scheduler thread at full CPU while the framework waits for it.\n\nAsh.Actions.Read.AsyncLimiter.await_at_least_one/1 (lib/ash/actions/read/async_limiter.ex) waited for concurrent async read tasks by polling each with Task.yield(task, 0) in a tight loop rather than blocking. While every outstanding task is still running (a slow related-data load or calculation), the loop returns immediately and repeats, busy-spinning and holding a BEAM scheduler at full CPU for the whole duration of the slow read; concurrent slow reads tie up further schedulers. The fix waits with Task.yield_many (a non-blocking sweep followed by a blocking wait with timeout: :infinity), so the process sleeps until a task completes instead of spinning.\n\nThis issue affects ash: from 2.19.0 before 3.32.2.","status":"published","published":"2026-09-01T03:37:24.292Z","modified":"2026-09-01T12:40:17.592Z","cvss":[{"version":"4.0","score":2.1,"vector":"CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N","level":"low","assessor":"cna"}],"cwes":["CWE-400"],"updated_at":"2026-11-02T13:40:35.004553Z"}],"euvd":[{"id":"EUVD-2026-68948","description":"Uncontrolled Resource Consumption vulnerability in ash-project ash lets a slow asynchronous read spin a scheduler thread at full CPU while the framework waits for it.\n\nAsh.Actions.Read.AsyncLimiter.await_at_least_one/1 (lib/ash/actions/read/async_limiter.ex) waited for concurrent async read tasks by polling each with Task.yield(task, 0) in a tight loop rather than blocking. While every outstanding task is still running (a slow related-data load or calculation), the loop returns immediately and repeats, busy-spinning and holding a BEAM scheduler at full CPU for the whole duration of the slow read; concurrent slow reads tie up further schedulers. The fix waits with Task.yield_many (a non-blocking sweep followed by a blocking wait with timeout: :infinity), so the process sleeps until a task completes instead of spinning.\n\nThis issue affects ash: from 2.19.0 before 3.32.2.","status":"published","published":"2026-09-01T03:37:24Z","modified":"2026-09-01T12:40:17Z","cvss":[{"version":"4.0","score":2.1,"vector":"CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N","level":"low"}],"updated_at":"2026-11-02T18:01:18.76029Z"}],"nvd":[{"id":"CVE-2026-82743","description":"Uncontrolled Resource Consumption vulnerability in ash-project ash lets a slow asynchronous read spin a scheduler thread at full CPU while the framework waits for it.\n\nAsh.Actions.Read.AsyncLimiter.await_at_least_one/1 (lib/ash/actions/read/async_limiter.ex) waited for concurrent async read tasks by polling each with Task.yield(task, 0) in a tight loop rather than blocking. While every outstanding task is still running (a slow related-data load or calculation), the loop returns immediately and repeats, busy-spinning and holding a BEAM scheduler at full CPU for the whole duration of the slow read; concurrent slow reads tie up further schedulers. The fix waits with Task.yield_many (a non-blocking sweep followed by a blocking wait with timeout: :infinity), so the process sleeps until a task completes instead of spinning.\n\nThis issue affects ash: from 2.19.0 before 3.32.2.","status":"published","published":"2026-09-01T04:18:04.363Z","modified":"2026-09-01T21:15:00.147Z","cvss":[{"version":"4.0","score":2.1,"vector":"CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"low","assessor":"secondary"}],"cwes":["CWE-400"],"updated_at":"2026-11-02T14:12:43.04945Z"}],"osv":[{"id":"CVE-2026-82743","title":"Ash.Actions.Read.AsyncLimiter busy-spins a scheduler while awaiting slow async reads","description":"Uncontrolled Resource Consumption vulnerability in ash-project ash lets a slow asynchronous read spin a scheduler thread at full CPU while the framework waits for it.\n\nAsh.Actions.Read.AsyncLimiter.await_at_least_one/1 (lib/ash/actions/read/async_limiter.ex) waited for concurrent async read tasks by polling each with Task.yield(task, 0) in a tight loop rather than blocking. While every outstanding task is still running (a slow related-data load or calculation), the loop returns immediately and repeats, busy-spinning and holding a BEAM scheduler at full CPU for the whole duration of the slow read; concurrent slow reads tie up further schedulers. The fix waits with Task.yield_many (a non-blocking sweep followed by a blocking wait with timeout: :infinity), so the process sleeps until a task completes instead of spinning.\n\nThis issue affects ash: from 2.19.0 before 3.32.2.","status":"published","published":"2026-09-01T03:37:24.292Z","modified":"2026-10-28T02:30:32.248519822Z","cvss":[{"version":"4.0","score":2.1,"vector":"CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N","level":"low"}],"cwes":["CWE-400"],"updated_at":"2026-11-02T15:45:18.482949Z"},{"id":"EEF-CVE-2026-82743","title":"Ash.Actions.Read.AsyncLimiter busy-spins a scheduler while awaiting slow async reads","description":"## Summary\n\nUncontrolled Resource Consumption vulnerability in ash-project ash lets a slow asynchronous read spin a scheduler thread at full CPU while the framework waits for it.\n\n`Ash.Actions.Read.AsyncLimiter.await_at_least_one/1` (`lib/ash/actions/read/async_limiter.ex`) waited for concurrent async read tasks by polling each with `Task.yield(task, 0)` in a tight loop rather than blocking. While every outstanding task is still running (a slow related-data load or calculation), the loop returns immediately and repeats, busy-spinning and holding a BEAM scheduler at full CPU for the whole duration of the slow read; concurrent slow reads tie up further schedulers. The fix waits with `Task.yield_many` (a non-blocking sweep followed by a blocking wait with `timeout: :infinity`), so the process sleeps until a task completes instead of spinning.\n\nThis issue affects ash: from 2.19.0 before 3.32.2.","status":"published","published":"2026-09-01T03:37:24.292Z","modified":"2026-09-08T03:30:04.239885341Z","cvss":[{"version":"4.0","score":2.1,"vector":"CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N","level":"low"}],"cwes":["CWE-400"],"updated_at":"2026-11-02T15:46:33.520522Z"}]}}