Foxit PDF Editor/Reader FoxitUpdater Race Condition Local Privilege Escalation Vulnerability

published 2026-09-23 last mo. modified 2026-10-08 last mo. also EUVD-2026-85161

cvss: 8.8; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.1%; EPSS 0.1% chance of exploitation in 30 days, percentile 0%
public exploits: 0; none known

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.

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CISA SSVC

Exploitation: none
Automatable: no
Technical impact: total
Assessed: last mo. (2026-09-23)

Exploit prediction

0.09% chance of exploitation in the next 30 days, higher than 0% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by	version	score	vector
CNA	3.1	8.8	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
NVD	3.1	7.8	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected products

Foxit Software Inc. Foxit PDF Editor
Foxit Software Inc. Foxit PDF Reader

Classification

Weakness

CWE-367 Time-of-check Time-of-use (TOCTOU) Race Condition

References

foxit.com /support/security-bulletins.html
vendor-advisory

Sources

CVE List CVE-2026-91813
NVD CVE-2026-91813

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