CVE-2026-64847
Description
A flaw was found in AnyIO. Untrusted or faulty worker code can write a large amount of data to the standard error (stderr) stream. This data fills a pipe that the parent process fails to drain, causing the process-pool call to block indefinitely. This can lead to a Denial of Service (DoS) condition, making the application unresponsive.
Statement
This vulnerability is rated as Moderate severity by Red Hat because triggering the denial of service requires executing worker tasks that generate substantial diagnostic output, impacting application availability without compromising system confidentiality or integrity. Within Red Hat supported products, AnyIO is deployed primarily as an internal concurrency component across containerized AI runtimes and automation services. A disruption occurs only when task execution paths produce enough unconsumed diagnostic streams to stall the process pool, limiting the blast radius to the affected asynchronous service.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 5.5 | N/A | N/A |
| Attack Vector | Local | N/A | N/A |
| Attack Complexity | Low | N/A | N/A |
| Privileges Required | Low | N/A | N/A |
| User Interaction | None | N/A | N/A |
| Scope | Unchanged | N/A | N/A |
| Confidentiality | None | N/A | N/A |
| Integrity Impact | None | N/A | N/A |
| Availability Impact | High | N/A | N/A |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Resource Consumption (CPU)
An unexpected call to blocking code can trigger an infinite loop, or a large loop that causes the software to pause and wait indefinitely.
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