CVE-2020-1933Network attack vector

Session-context script execution via unescaped template errors

Published Jan 28, 2020 · Updated Aug 4, 2024

Cross-site scripting in Apache NiFi 1.0.0 through 1.10.0 allows remote attackers to run JavaScript in an authenticated user's Firefox session. ProcessGroupResource embeds exception messages produced during malformed template upload or import into an XML error response without HTML escaping. Execution requires an authenticated user to act on a crafted template in Firefox, and the script runs in that user's NiFi UI context.

CVSS severity6.1
Medium
EPSS probability2.81%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cross-site scripting in Apache NiFi 1.0.0 through 1.10.0 allows remote attackers to run JavaScript in an authenticated user's Firefox session. ProcessGroupResource embeds exception messages produced during malformed template upload or import into an XML error response without HTML escaping. Execution requires an authenticated user to act on a crafted template in Firefox, and the script runs in that user's NiFi UI context.

The record

CVE
CVE-2020-1933
Published
Jan 28, 2020
Updated
Aug 4, 2024
Vendor
The Apache Software Foundation
Product
Apache NiFi
Classifications
CWE-79, T1059.007
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 28, 2020CVE 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=Apache NiFi 1.0.0 to 1.10.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Apache Software Foundation · Apache NiFiversion=Apache NiFi 1.0.0 to 1.10.0

Published CVSS scores

6.1GitHub Security Advisory DatabaseCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1059.007Command and Scripting Interpreter: JavaScript

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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