CVE-2021-38680Network attack vector

Reflected XSS via unsanitized request input

Published Dec 29, 2021 · Updated Sep 16, 2024

Kazoo Server before 4.11.20 allows remote attackers to inject script through a reflected cross-site scripting flaw. The vulnerable web response reflects attacker-controlled input without adequate output encoding, causing a victim browser to execute the injected code when it follows a crafted request. Exploitation requires remote delivery and victim interaction; the published advisory does not identify the affected endpoint or any ability beyond script execution in the victim browser.

CVSS severity6.1
Medium
EPSS probability0.69%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Kazoo Server before 4.11.20 allows remote attackers to inject script through a reflected cross-site scripting flaw. The vulnerable web response reflects attacker-controlled input without adequate output encoding, causing a victim browser to execute the injected code when it follows a crafted request. Exploitation requires remote delivery and victim interaction; the published advisory does not identify the affected endpoint or any ability beyond script execution in the victim browser.

The record

CVE
CVE-2021-38680
Published
Dec 29, 2021
Updated
Sep 16, 2024
Vendor
Linn Products Limited
Product
Kazoo Server
Classifications
CWE-79, T1189
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 29, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 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 <4.11.20

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Linn Products Limited · Kazoo Serverversion=unspecified <4.11.20

Published CVSS scores

5.3NVDCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N
4.3NVDAV:N/AC:M/Au:N/C:N/I:P/A:N
6.1NVDCVSS: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 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 exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1189Drive-by Compromise

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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