CVE-2018-21035 describes a denial-of-service vulnerability in the WebSocket implementation of Qt through version 5.14.1. The flaw allows attackers to exhaust system memory by sending large WebSocket frames or messages, up to 2GB each, as the limits cannot be configured to smaller values. This unauthenticated attack has a CVSS score of 7.5 (High) due to its network-based vector and high impact on availability. There is currently no evidence of active exploitation, public exploit code, or significant community discussion surrounding this vulnerability.
| Vendor | Product | Version(s) | CPE |
|---|---|---|---|
<= 5.14.1CPE matchmatch criteria | cpe:2.3:a:qt:qt:*:*:*:*:*:*:*:* |
CVSS version used by this source: 3.0
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
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The average CVE in this peer group has 0.1 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.
In Qt through 5.14.1 the WebSocket implementation accepts up to 2GB for frames and 2GB for messages. Smaller limits cannot be configured. This makes it easier for attackers to cause a denial of service (memory consumption).
Feb 11, 2020qt5-qtwebsockets: websocket implementation allows only limited size for frames and messages therefore attacker can cause DOS
Sep 23, 2018