CVE-2018-21035

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).

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 3.0 •
CVSS 2.0 •
EPSS 0.43%
Third-Party Advisory qt.io Third-Party Advisory qt-project.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://codereview.qt-project.org/c/qt/qtwebsockets/+/284735 third party advisory patch
https://bugreports.qt.io/browse/QTBUG-70693 third party advisory exploit

Frequently Asked Questions

What is the severity of CVE-2018-21035?
CVE-2018-21035 has been scored as a high severity vulnerability.
How to fix CVE-2018-21035?
To fix CVE-2018-21035, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2018-21035 being actively exploited in the wild?
It is possible that CVE-2018-21035 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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