CVE-2021-21870

mediumpriority · track · 36EPSS 0.019 · 79 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

1.89% (79th) EPSS

CVSS 6.8 · medium

Is it mine?

2 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-27

A use-after-free vulnerability exists in the JavaScript engine of Foxit Software’s PDF Reader, version 10.1.4.37651. A specially crafted PDF document can trigger the reuse of previously free memory, which can lead to arbitrary code execution. An attacker needs to trick the user into opening a malicious file or site to trigger this vulnerability if the browser plugin extension is enabled.

cvss

Technical severity, 0–10. One row per scoring source.

8.8

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.8–8.8

v2.06.8mediumAV:N/AC:M/Au:N/C:P/I:P/A:Pprimary · NVD / NIST USexploitability 8.6 · impact 6.4

v3.18.8highCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 2.8 · impact 5.9

v3.08.8highCVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:Hsecondary · ENISA EU

v3.08.8highCVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:Hsecondary · talos-cna@cisco.com USexploitability 2.8 · impact 5.9

v3.18.1highCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-416USprimary

affected products (2)

Products and version ranges known to be affected.

n/a Foxit≤ Foxit Reader 10.1.4.37651enisa_euvdEU
foxit pdf reader= 10.1.4.37651nvdUScpe:2.3:a:foxit:pdf_reader:*:*:*:*:*:*:*:*

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd NVD CVE.org MITRE

published 2021-08-05modified 2026-06-17

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+12230 more

references (5)

External citations — patches, advisories, analysis.

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