CVE-2023-33866Public exploitNetwork attack vector

Arbitrary code execution via OnBlur use-after-free

Published Jul 19, 2023 · Updated Nov 4, 2025

Use-after-free in Foxit PDF Reader 12.1.2.15332 and earlier allows remote attackers to execute arbitrary code through a crafted PDF. An OnBlur form-field callback calls deletePages, frees page-associated objects, queues another setFocus event, and later reuses the freed memory. Exploitation requires a user to open the document, or to visit a malicious site when the browser plugin is enabled, and executes code in that user's context.

CVSS severity8.8
High
EPSS probability0.92%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Use-after-free in Foxit PDF Reader 12.1.2.15332 and earlier allows remote attackers to execute arbitrary code through a crafted PDF. An OnBlur form-field callback calls deletePages, frees page-associated objects, queues another setFocus event, and later reuses the freed memory. Exploitation requires a user to open the document, or to visit a malicious site when the browser plugin is enabled, and executes code in that user's context.

The record

CVE
CVE-2023-33866
Published
Jul 19, 2023
Updated
Nov 4, 2025
Vendor
Foxit Software
Product
Foxit PDF Reader
Classifications
CWE-416, T1204.002
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 19, 2023CVE publishedPublication date reported by the CVE source.
  2. Nov 4, 2025Record 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=12.1.2.15332

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Foxit Software · Foxit PDF Readerversion=12.1.2.15332

Published CVSS scores

8.8Cisco TalosCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/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.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-416Use After Free
T1204.002Malicious File

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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