---
id: CVE-2026-73108
title: >-
  RustDesk versions before 1.4.7 contain an uncontrolled speculative memory
  allocation vulnerability in BytesCodec
summary: >-
  RustDesk versions before 1.4.7 contain an uncontrolled speculative memory
  allocation vulnerability in BytesCodec. Before authentication, the decoder
  trusts the payload length encoded in a four-byte frame header and reserves
  that amount b…
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-770
published: '2026-08-26'
updated: '2026-09-23'
sourceUpdated: '2026-09-23T17:17:45.540'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-73108'
references:
  - url: >-
      https://github.com/rustdesk/hbb_common/commit/547da54b4ee58eed47163fbd47edb4639e3d88de
    label: disclosure@vulncheck.com
  - url: >-
      https://github.com/rustdesk/rustdesk/commit/518296f2570d107ad416f29ade5fcce3177f4115
    label: disclosure@vulncheck.com
  - url: 'https://github.com/rustdesk/rustdesk/releases/tag/1.4.7'
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/rustdesk-uncontrolled-memory-allocation-dos-via-bytescodec
    label: disclosure@vulncheck.com
tags:
  - nvd
epss: 0.00766
epssPercentile: 0.53515
ingestedAt: '2026-08-29T21:42:34.561Z'
---

## Overview

RustDesk versions before 1.4.7 contain an uncontrolled speculative memory allocation vulnerability in BytesCodec. Before authentication, the decoder trusts the payload length encoded in a four-byte frame header and reserves that amount before receiving the payload. A crafted header can request up to 1,073,741,823 bytes of capacity, allowing unauthenticated attackers to use concurrent TCP connections to cause memory exhaustion and denial of service. The fix caps header-triggered speculative preallocation at 256 KiB.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.