Skip to main content
No exploitation reported

CVE-2021-21798

No exploitation reported by the sources we read.

  • Published2021-09-15
  • WeaknessCWE-562

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

An exploitable return of stack variable address vulnerability exists in the JavaScript implementation of Nitro Pro PDF. A specially crafted document can cause a stack variable to go out of scope, resulting in the application dereferencing a stale pointer. This can lead to code execution under the context of the application. An attacker can convince a user to open a document to trigger the vulnerability.

Timeline

dates in UTC
  1. 2021-09-1514:15CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-11-03 15:37 UTC
Indicators tagged with this CVE, per day0 indicators over 7 days
Block these indicators
  • Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2021-21798?format=txt
  • CSV export: https://api.ismalicious.com/edl/cve/CVE-2021-21798?format=csv
  • TAXII collection of exploited CVEs
  • The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD
Gonitro nitro pro
BranchAffectedFixed in
13.31= 13.31.0.605no fix published
13.33= 13.33.2.645no fix published

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Fix

No fix published by the sources we read yet. NVD record

Detection

Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof-of-concept repositories
none listed
PoC-in-GitHub
Metasploit modules
none listed
Metasploit Framework

Sources

  • NVDCVSS 3.17.8read 2026-10-23
  • CNACVSS 3.08.8known since 2026-10-23
  • NVDCVSS 2.06.8read 2026-10-23
  • CNAweakness (CWE)CWE-562known since 2026-10-23
  • FIRST EPSSEPSS score21.4 %read 2026-11-02

Identifiers

Technical details

CVSS v3 Vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Published
2021-09-15
Last Modified
2026-06-17
NVD status
Modified

Frequently asked questions

What is CVE-2021-21798?

An exploitable return of stack variable address vulnerability exists in the JavaScript implementation of Nitro Pro PDF. A specially crafted document can cause a stack variable to go out of scope, resulting in the application dereferencing a stale pointer. This can lead to code execution under the context of the application. An attacker can convince a user to open a document to trigger the vulnerability.

Is CVE-2021-21798 actively exploited?

Active exploitation of CVE-2021-21798 has not been confirmed. Its EPSS score was 21.4% on 2026-11-03, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2021-21798?

CVE-2021-21798 has a CVSS v3 base score of 7.8 (HIGH severity), with vector string CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

Hear about the next vulnerability in your software

Surveillance reads the versions in your stack — a domain, a lockfile or a list — checks each CVE against the ranges its sources publish, and alerts you when one you run is exploited or enters CISA KEV. A version it cannot read stays « version not verified ».

Get alerts for this productCISA KEV additions, October 2026Search CVEs

No credit card required · No monthly cap on website lookups · 250 API requests/month

Go further

Related vulnerabilities

Same product first, then the same vendor advisory and the same publication week.

Back to CVE Database

Sources for this record