The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - cbor2 provides encoding and decoding for the Concise Binary Object Representation (CBOR) serialization     format. Versions prior to 5.9.0 are vulnerable to a Denial of Service (DoS) attack caused by uncontrolled     recursion when decoding deeply nested CBOR structures. This vulnerability affects both the pure Python     implementation and the C extension `_cbor2`. The C extension relies on Python's internal recursion limits     `Py_EnterRecursiveCall` rather than a data-driven depth limit, meaning it still raises `RecursionError`     and crashes the worker process when the limit is hit. While the library handles moderate nesting levels,     it lacks a hard depth limit. An attacker can supply a crafted CBOR payload containing approximately     100,000 nested arrays `0x81`. When `cbor2.loads()` attempts to parse this, it hits the Python     interpreter's maximum recursion depth or exhausts the stack, causing the process to crash with a     `RecursionError`. Because the library does not enforce its own limits, it allows an external attacker to     exhaust the host application's stack resource. In many web application servers (e.g., Gunicorn, Uvicorn)     or task queues (Celery), an unhandled `RecursionError` terminates the worker process immediately. By     sending a stream of these small (<100KB) malicious packets, an attacker can repeatedly crash worker     processes, resulting in a complete Denial of Service for the application. Version 5.9.0 patches the issue.
    (CVE-2026-26209)

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Linux Distros Unpatched Vulnerability : CVE-2026-26209

high Nessus Plugin ID 303649

Version 1.3

Version 1.2

Version 1.1

Version 1.3 Apr 1, 2026, 4:53 PM Detection (updated detection logic) Plugin metadata Plugin Feed: 202604011653
Version 1.2 Mar 26, 2026, 6:10 PM Detection (updated detection logic) Plugin metadata Plugin Feed: 202603261810
Version 1.1 Mar 26, 2026, 1:29 AM New Plugin Feed: 202603260129