CVE-2026-91804: A heap-based out-of-bounds write vulnerability exists in Foxit PDF Editor/Reader’s rendering of Circle annotat

Q: How do I fix CVE-2026-91804?

pdf editor: upgrade to newer than 2026.2.0.39747; pdf reader: upgrade to newer than 2026.2.0.39747. Exact commands for each OS are on this page.

Q: Is CVE-2026-91804 being exploited?

CVE-2026-91804 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2026-91804 affect?

CVE-2026-91804 affects pdf editor, pdf reader. Severity is high (CVSS 7.8). A heap-based out-of-bounds write vulnerability exists in Foxit PDF Editor/Reader’s rendering of Circle annotations with malformed Cloudy appearance streams in specially crafted PDF files. Insufficient validation of the appearance geometry c

Routine

HIGH 7.8UPGRADEUPGRADE

CVE-2026-91804 is a high-severity flaw (CVSS 7.8) affecting pdf editor, pdf reader. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

A heap-based out-of-bounds write vulnerability exists in Foxit PDF Editor/Reader’s rendering of Circle annotations with malformed Cloudy appearance streams in specially crafted PDF files. Insufficient validation of the appearance geometry can result in memory corruption and application crashes.

Why this priority

High severity

A fixed release or distro patch exists.

Risk facts

CVSS score	7.8 (High)
Attack vector	Local
Attack complexity	Low
Privileges needed	None
User interaction	Required
EPSS exploit chance	0.2% (top 94%)
CISA exploited list	No
Weakness	CWE-787
Published	2026-09-23
Last modified	2026-10-08

Publisher (CNA): Foxit · Vendor: foxit

Last updated 2026-10-08 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-09-23 08:17 UTCPublished CVE record published
2026-10-08 13:58 UTCUpdated Record last modified

foxit pdf editor UPGRADE

Affected: <= 13.2.5.63482 · >= 14.0.0.33046 and <= 14.0.7.33751 · >= 2023.1.0.15510 and <= 2023.3.0.23028 · >= 2024.1.0.23997 and <= 2024.4.1.27687 · >= 2025.1.0.27937 and <= 2025.3.0.35737 · >= 2026.1.0.36452 and <= 2026.2.0.39747

Fixed in: newer than 2026.2.0.39747

Safe to downgrade to: a release before 14.0.0.33046

1. Check installed version

apt-cache policy pdf-editor || rpm -q pdf-editor || pdf-editor --version

2. UPGRADE to newer than 2026.2.0.39747 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade pdf-editor

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade pdf-editor

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

3. If no update is available yet, DOWNGRADE to a release before 14.0.0.33046 (Debian / Ubuntu)

apt-cache madison pdf-editor sudo apt install pdf-editor=<VERSION_BEFORE_14.0.0.33046> sudo apt-mark hold pdf-editor

3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list pdf-editor sudo dnf downgrade pdf-editor-<VERSION_BEFORE_14.0.0.33046> sudo dnf versionlock add pdf-editor

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.

foxit pdf reader UPGRADE

Affected: <= 2026.2.0.39747

Fixed in: newer than 2026.2.0.39747

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy pdf-reader || rpm -q pdf-reader || pdf-reader --version

2. UPGRADE to newer than 2026.2.0.39747 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade pdf-reader

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade pdf-reader

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

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-2026-91804?

pdf editor: upgrade to newer than 2026.2.0.39747; pdf reader: upgrade to newer than 2026.2.0.39747. Exact commands for each OS are on this page.

Is CVE-2026-91804 being exploited?

CVE-2026-91804 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-2026-91804 affect?

CVE-2026-91804 affects pdf editor, pdf reader. Severity is high (CVSS 7.8). A heap-based out-of-bounds write vulnerability exists in Foxit PDF Editor/Reader’s rendering of Circle annotations with malformed Cloudy appearance streams in specially crafted PDF files. Insufficient validation of the appearance geometry c

How urgent is CVE-2026-91804?

Priority 29/100. High severity

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References

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