What’s Vulnerable › Vulnerabilities

CVE-2026-82743: Ash.Actions.Read.AsyncLimiter busy-spins a scheduler while awaiting slow async reads

• Severity: low (CVSS 2.1 v4.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-09-01 · updated 2026-09-01
• Weakness: CWE-400

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. 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. This issue affects ash: from 2.19.0 before 3.32.2.

Affected products

• ash-project ash: from 2.19.0 before 3.32.2 — fixed in 3.32.2

How to fix

Upgrade to a fixed version: ash-project ash 3.32.2. Check the vendor advisory for mitigations.

References

• https://cna.erlef.org/cves/CVE-2026-82743.html
• https://github.com/ash-project/ash/commit/0a5ecd2ffdfa848afdeb8827f02982ef2a63a1cd
• https://github.com/ash-project/ash/security/advisories/GHSA-33wq-x3q2-c92h
• https://osv.dev/vulnerability/EEF-CVE-2026-82743
• https://github.com/ash-project/ash/security/advisories/GHSA-33wq-x3q2-c92h

Get alerted when CVE-2026-82743 or the next vulnerability affects your stack