How severe is CVE-2026-91813?

CVE-2026-91813 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-91813 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (1st percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-91813?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2026-91813 published?

CVE-2026-91813 was published on 2026-09-23.

CVE-2026-91813

CVE-2026-91813 is a high-severity vulnerability with a CVSS 3.x base score of 8.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-367.

Key facts

Severity: High (CVSS 3.x base score 8.8)
EPSS exploit prediction: 0% (1st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-367
Published: 2026-09-23
Last modified: 2026-09-23

Description

A vulnerability in Foxit PDF Editor/Reader’s update mechanism allows an update package to be replaced between download and high-privilege extraction due to insufficient file locking and integrity validation. This could enable local attackers to execute arbitrary code with elevated privileges.

Frequently asked questions

What is CVE-2026-91813?: A vulnerability in Foxit PDF Editor/Reader’s update mechanism allows an update package to be replaced between download and high-privilege extraction due to insufficient file locking and integrity validation. This could enable local attackers to execute arbitrary code with elevated privileges.
How severe is CVE-2026-91813?: CVE-2026-91813 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-91813 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (1st percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-91813?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2026-91813 published?: CVE-2026-91813 was published on 2026-09-23.

References

https://www.foxit.com/support/security-bulletins.html

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