CVE-2026-91817

Information disclosure and crash via string deletion underflow

Published Sep 23, 2026 · Updated Sep 23, 2026

Out-of-bounds read in Foxit PDF Reader and PDF Editor 2026.2 and earlier allows attackers to disclose memory or crash the application. Embedded PDF JavaScript can supply an invalid wide-string deletion range whose unchecked arithmetic underflows before a heap read. Exploitation requires a user to open a crafted PDF; affected Editor branches also include 13.2.6 and earlier and 14.0.7 and earlier.

CVSS severity6.1
Medium
EPSS probability0.11%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Out-of-bounds read in Foxit PDF Reader and PDF Editor 2026.2 and earlier allows attackers to disclose memory or crash the application. Embedded PDF JavaScript can supply an invalid wide-string deletion range whose unchecked arithmetic underflows before a heap read. Exploitation requires a user to open a crafted PDF; affected Editor branches also include 13.2.6 and earlier and 14.0.7 and earlier.

The record

CVE
CVE-2026-91817
Published
Sep 23, 2026
Updated
Sep 23, 2026
Vendor
Foxit Software Company
Product
Foxit PDF Reader
Classifications
CWE-125, T1204.002
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 23, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 23, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=Versions 2026.2 and earlier

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Foxit Software Company · Foxit PDF Readerversion=Versions 2026.2 and earlier
Foxit Software Company · Foxit PDF Editorversion=Versions 13.2.6 and earlier; version=Versions 14.0.7 and earlier; version=Versions 2026.2 and earlier

Published CVSS scores

6.1Foxit SoftwareCVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Activity data is delayed. The latest report is Sep 28, 2026.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-125Out-of-bounds Read
T1204.002User Execution: Malicious File

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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