CVE-2021-34966

Code execution via stale FileAttachment annotation object

Published May 7, 2024 · Updated Aug 4, 2024

Use-after-free in Foxit PDF Editor 11.0.0.49893 allows remote attackers to execute code through a crafted PDF that a user opens. The FileAttachment annotation handler operates on an Annotation object without first confirming that the object still exists, allowing access to freed object memory. The target must visit a malicious page or open a malicious file, after which code runs in the current application process.

CVSS severity7.8
High
EPSS probability0.35%
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 Editor 11.0.0.49893 allows remote attackers to execute code through a crafted PDF that a user opens. The FileAttachment annotation handler operates on an Annotation object without first confirming that the object still exists, allowing access to freed object memory. The target must visit a malicious page or open a malicious file, after which code runs in the current application process.

The record

CVE
CVE-2021-34966
Published
May 7, 2024
Updated
Aug 4, 2024
Vendor
Foxit Software
Product
Foxit PDF Editor
Classifications
CWE-416, T1203
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 7, 2024CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record 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=-
  2. Affected versionversion=11.0.0.49893

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Foxit Software · Foxit PDF Editorversion=-; version=11.0.0.49893

Published CVSS scores

7.8Zero Day InitiativeCVSS:3.0/AV:L/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)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-416Use After Free
T1203Exploitation for Client Execution

Public exploit references

No public exploit references are available in this record.

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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