Skip to content
Fencer Intel
medium 5.4

CVE-2021-21087 json

ColdFusion Improper neutralization of web input during page generation could lead to arbitrary JavaScript execution in the browser

published 5y ago modified 4mo ago also EUVD-2021-8478

cvss
5.4
version 3.0, CNA
cisa kev
Not listed
not in CISA's catalog
epss
37.1%
EPSS 37.1% chance of exploitation in 30 days, percentile 98%
public exploits
0
none known, plus a Nuclei check

Summary

Adobe Coldfusion versions 2016 (update 16 and earlier), 2018 (update 10 and earlier) and 2021.0.0.323925 are affected by an Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability. An attacker could abuse this vulnerability to execute arbitrary JavaScript code in context of the current user. Exploitation of this issue requires user interaction.

Patch / fix

Is CVE-2021-21087 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

Check with Fencer

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
last yr.

Exploit prediction

37.10% chance of exploitation in the next 30 days, higher than 98% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

CVSS scores

assigned by version score vector
CNA 3.0 5.4 CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
NVD 3.1 5.4 CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
NVD 2.0 3.5 AV:N/AC:M/Au:S/C:N/I:P/A:N

Affected products

  • Adobe ColdFusion

Classification

Weakness
  • CWE-79 Improper Neutralization of Input During Web Page Generation

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.