CVE-2020-8120Public exploitNetwork attack vector

Browser script execution via unescaped SVG color

Published Feb 4, 2020 · Updated Aug 4, 2024

Reflected cross-site scripting in Nextcloud Server 16.0.1 allows remote attackers to execute script in a user's browser via a crafted SVG logo URL. The SVG generator inserts the color path parameter into the generated logo markup without neutralizing attacker-supplied markup. Exploitation requires a user to open the crafted URL; injected script runs in the Nextcloud origin and can read or alter data available to that session.

CVSS severity6.1
Medium
EPSS probability0.92%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Reflected cross-site scripting in Nextcloud Server 16.0.1 allows remote attackers to execute script in a user's browser via a crafted SVG logo URL. The SVG generator inserts the color path parameter into the generated logo markup without neutralizing attacker-supplied markup. Exploitation requires a user to open the crafted URL; injected script runs in the Nextcloud origin and can read or alter data available to that session.

The record

CVE
CVE-2020-8120
Published
Feb 4, 2020
Updated
Aug 4, 2024
Vendor
Nextcloud GmbH
Product
Nextcloud Server
Classifications
CWE-79, T1189
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 4, 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=16.0.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Nextcloud GmbH · Nextcloud Serverversion=16.0.1

Published CVSS scores

6.1NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
4.3NIST NVDAV:N/AC:M/Au:N/C:N/I:P/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 exploitPublished

Weakness, pattern, technique

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

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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