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🛡️ CVE-2021-30818 on Ubuntu — qtwebkit-opensource-src

⚪ Unknown ✅ No Known Exploit OSV
N/A
CVSS Score
0 Low4 Medium7 High9 Critical10

Description

A type confusion issue was addressed with improved state handling. This issue is fixed in iOS 14.8 and iPadOS 14.8, tvOS 15, iOS 15 and iPadOS 15, Safari 15, watchOS 8. Processing maliciously crafted web content may lead to arbitrary code execution.

Distribution advisory

This page covers CVE-2021-30818 as tracked by Ubuntu, for the package qtwebkit-opensource-src. The fix is available in version 2.34.0-1ubuntu1; earlier versions remain affected.

How this vulnerability can be exploited

This issue can be reached over the network, attack complexity is low, an attacker needs no privileges on the target. A user must be tricked into taking some action. The scope is unchanged, so the impact stays within the vulnerable component. Rated impact: confidentiality high, integrity high, availability high.

CVSS metrics in full

The score comes from this vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

  • Attack vector: Network — reachable from anywhere that can route to the service.
  • Attack complexity: Low — the attack works reliably, with no preparation.
  • Privileges required: None — an unauthenticated stranger can try it.
  • User interaction: Required — someone has to click, open or visit something.
  • Scope: Unchanged — the damage stays inside the vulnerable component.
  • Confidentiality impact: High — total loss, or loss the attacker controls.
  • Integrity impact: High — total loss, or loss the attacker controls.
  • Availability impact: High — total loss, or loss the attacker controls.

Affected software

UBUNTU-CVE-2021-30818 is recorded against 5 packages.

  • qtwebkit-opensource-src
  • qtwebkit-source
  • webkit2gtk (fixed in 2.34.0-1ubuntu1)
  • webkitgtk
  • wpewebkit

Timeline and source

Published on 28 October 2021 and last revised on 22 April 2026. No public exploit is currently recorded for this entry. Record sourced from OSV.

References

ubuntu.com (Report)
webkitgtk.org (Report)
www.cve.org (Report)

Other advisories for this package

qtwebkit-opensource-src has other advisories on record. If you are patching this one, these are worth checking on the same host:

CVE-2021-30818 on other distributions

Each distribution ships its own build and its own fixed version. Pick the one you run:

Details

Severity Unknown
CVSS Score N/A
CVSS Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CWE N/A
Public Exploit ✅ No
Source OSV
Published 2021-10-28
Updated 2026-08-20
Modified 2026-04-22
Fix URL N/A

Affected Packages

Software From version Fixed in
qtwebkit-opensource-src — —
qtwebkit-source — —
webkit2gtk — 2.34.0-1ubuntu1
webkitgtk — —
wpewebkit — —

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ⓘ Data Notice: The information presented above has been compiled from publicly available internet sources. Boteraser aggregates this data solely for informational purposes and does not independently classify, evaluate, or endorse any findings about the vulnerabilities listed. The accuracy and completeness of this information is the sole responsibility of the original publishers. Boteraser and its operators accept no liability for any decisions made based on this data.

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