8.6

CVE-2018-21035: qt

CVSS: 8.6v3.0HighModified
AliasesMGASA-2021-0270UBUNTU-CVE-2018-21035DEBIAN-CVE-2018-21035
Published 28-02-2020Last modified 05-08-2024
Open JSON

Vulnerability summary

CVE-2018-21035 is a high (CVSS 8.6) vulnerability in qt. EPSS estimates a 2.34% chance of exploitation in the next 30 days, higher than 83.3% of scored vulnerabilities. 1 public exploit is recorded.

Overall risk
45/100
0100
Medium · default modelHow is this calculated?
CVSS score
8.6/10
010
High · v3.0 (CVE.org)
EPSS score
2.34%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits1reference

Advisory lineage

Upstream 0 · Downstream 1
RHSA-2020:4690

Timeline

  1. 28-02-2020
    PublishedVulnerability first disclosed.
  2. 05-08-2024
    Last modifiedVulnerability information updated.

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 metrics

7 scores · 4 sources · 3 versions

EPSS trend

Probability

2.34%

Chance of exploitation in the next 30 days

Percentile

83%

Versus all other CVEs

30-day change

0.00 pp

From 2.34% on 18-09-2026

18-09-202618-10-2026
EPSS score
2.34%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

1 found
  • referenceUnverified

    Exploit Reference (bugreports.qt.io)

    Maturity: unknown

Weaknesses

CWE · root cause

Affected systems

Debian1 product
  • qtwebsockets-opensource-src< 5.15.1-2
Mageia1 product
  • qtwebsockets5< 5.12.6-1.1.mga7
Qt1 product
  • qt≤ 5.14.1
Ubuntu1 product
  • qtwebsockets-opensource-srcAll versions (No fix recorded)

4 vendors · 4 products

References

9 links