CVE-2018-21035
This makes it easier for attackers to cause a denial of service (memory consumption).
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (2.34%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
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).
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 2.34% probability · 84th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-770
- Affected
- qt/qt
- Source
- cve@mitre.org
EPSS 2.3% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://bugreports.qt.io/browse/QTBUG-70693Exploit, Third Party Advisory
- https://codereview.qt-project.org/c/qt/qtwebsockets/+/284735Patch, Third Party Advisory
- https://bugreports.qt.io/browse/QTBUG-70693Exploit, Third Party Advisory
- https://codereview.qt-project.org/c/qt/qtwebsockets/+/284735Patch, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.