CVE-2021-23784Public exploitNetwork attack vector

Cross-site scripting via unescaped array input

Published Nov 3, 2021 · Updated Sep 17, 2024

Cross-site scripting in Luke Edwards Tempura before 0.4.0 allows remote attackers to execute JavaScript via crafted array input. The esc function returns object values, including arrays, without converting their contents to a string and applying HTML escaping. Exploitation requires a consuming application to pass attacker-controlled array data through esc and a user to load the resulting HTML.

CVSS severity6.1
Medium
EPSS probability1.26%
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 Luke Edwards Tempura before 0.4.0 allows remote attackers to execute JavaScript via crafted array input. The esc function returns object values, including arrays, without converting their contents to a string and applying HTML escaping. Exploitation requires a consuming application to pass attacker-controlled array data through esc and a user to load the resulting HTML.

The record

CVE
CVE-2021-23784
Published
Nov 3, 2021
Updated
Sep 17, 2024
Vendor
Luke Edwards
Product
Tempura
Classifications
CWE-79, T1203
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Nov 3, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 17, 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=unspecified <0.4.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Luke Edwards · Tempuraversion=unspecified <0.4.0

Published CVSS scores

6.1GitHub 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.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1203Exploitation for Client Execution

Public exploit references

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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