CVE-2021-34970

Information disclosure via malformed format specifiers

Published May 7, 2024 · Updated Aug 4, 2024

Foxit PDF Reader 11.0.1.49938 and earlier and affected PDF Editor builds allow attackers to disclose process data through a crafted PDF. The JavaScript print path passes a user-controlled string to util.printf, which mishandles format extensions instead of validating the string before interpreting it. Exploitation requires user interaction to open the file or visit the page; alone, the flaw discloses data, while code execution requires another vulnerability.

CVSS severity5.5
Medium
EPSS probability0.33%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Foxit PDF Reader 11.0.1.49938 and earlier and affected PDF Editor builds allow attackers to disclose process data through a crafted PDF. The JavaScript print path passes a user-controlled string to util.printf, which mishandles format extensions instead of validating the string before interpreting it. Exploitation requires user interaction to open the file or visit the page; alone, the flaw discloses data, while code execution requires another vulnerability.

The record

CVE
CVE-2021-34970
Published
May 7, 2024
Updated
Aug 4, 2024
Vendor
Foxit Software
Product
Foxit PDF Reader
Classifications
CWE-134, T1203, T1204.002
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=- <=11.0.1.49938
  2. Affected versionversion=11.0.1.49938

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Foxit Software · Foxit PDF Readerversion=- <=11.0.1.49938; version=11.0.1.49938
Foxit Software · Foxit PDF Editorversion=- <=10.1.5.37672; version=11.0.0.49893; version=11.0.1.49938

Published CVSS scores

3.3Zero Day InitiativeCVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N

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.

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

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-134Use of Externally-Controlled Format String
T1203Exploitation for Client Execution
T1204.002Malicious File

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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