CVE-2021-28025: Integer Overflow vulnerability in qsvghandler.cpp in Qt qtsvg versions 5.15.1, 6.0.0, 6.0.2, and 6.2, allows l

Routine

MEDIUM 5.5DOWNGRADE

CVE-2021-28025 is a medium-severity flaw (CVSS 5.5) affecting qt. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

Integer Overflow vulnerability in qsvghandler.cpp in Qt qtsvg versions 5.15.1, 6.0.0, 6.0.2, and 6.2, allows local attackers to cause a denial of service (DoS).

Why this priority

Public exploit reference

No fix is published yet: follow the downgrade or mitigation steps.

Risk facts

CVSS score	5.5 (Medium)
Attack vector	Local
Attack complexity	Low
Privileges needed	None
User interaction	Required
EPSS exploit chance	0.3% (top 79%)
CISA exploited list	No
Weakness	CWE-190
Published	2023-08-11
Last modified	2026-06-17

Publisher (CNA): MITRE · Vendor: qt

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2023-08-11 14:15 UTCPublished CVE record published
2026-06-17 03:45 UTCUpdated Record last modified

qt qt DOWNGRADE

Affected: 5.15.1 · 6.0.0 · 6.0.0 alpha1 · 6.0.0 beta1 · 6.0.0 beta2 · 6.0.0 beta3 · 6.0.0 beta4 · 6.0.0 beta5

Fixed in: no fixed release known

Safe to downgrade to: a release before 5.15.1

1. Check installed version

apt-cache policy qt || rpm -q qt || qt --version

2. No fixed release: DOWNGRADE to a release before 5.15.1 (Debian / Ubuntu)

apt-cache madison qt sudo apt install qt=<VERSION_BEFORE_5.15.1> sudo apt-mark hold qt

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list qt sudo dnf downgrade qt-<VERSION_BEFORE_5.15.1> sudo dnf versionlock add qt

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2021-28025?

qt: downgrade or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2021-28025 being exploited?

CVE-2021-28025 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2021-28025 affect?

CVE-2021-28025 affects qt. Severity is medium (CVSS 5.5). Integer Overflow vulnerability in qsvghandler.cpp in Qt qtsvg versions 5.15.1, 6.0.0, 6.0.2, and 6.2, allows local attackers to cause a denial of service (DoS).

How urgent is CVE-2021-28025?

Priority 30/100. Public exploit reference

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References

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