CVE-2021-21797

mediumpriority · track · 36EPSS 0.150 · 97 %ileEUUS

grimoire priorityP1 · Urgent

Exploitable?

—

no known exploitation

Likely / severe?

15.0% (97th) EPSS

CVSS 6.8 · medium

Is it mine?

3 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-27

An exploitable double-free vulnerability exists in the JavaScript implementation of Nitro Pro PDF. A specially crafted document can cause a reference to a timeout object to be stored in two different places. When closed, the document will result in the reference being released twice. This can lead to code execution under the context of the application. An attacker can convince a user to open a document to trigger this vulnerability.

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

v3.17.8highCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 1.8 · 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

v3.17.1highCVSS:3.1/AV:L/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-415USprimary

affected products (3)

Products and version ranges known to be affected.

n/a Nitro Pro≤ Nitro Pro 13.31.0.605 ,Nitro Pro 13.33.2.645enisa_euvdEU
gonitro nitro pro= 13.31.0.605nvdUScpe:2.3:a:gonitro:nitro_pro:*:*:*:*:*:*:*:*
gonitro nitro pro= 13.33.2.645nvdUScpe:2.3:a:gonitro:nitro_pro:*:*:*:*:*:*:*:*

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 2021-10-18modified 2026-06-17

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+1203 more

references (6)

External citations — patches, advisories, analysis.

scry

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