CVE-2023-3973Network attack vector

Script execution via unsanitized diagram labels

Published Jul 27, 2023 · Updated Oct 15, 2024

Reflected XSS in draw.io before 21.6.3 allows remote attackers to execute script in a victim's browser through crafted diagram content. The label-rendering path accepts HTML markup in diagram labels without passing it through the added DOMPurify sanitization. Exploitation requires a victim to open attacker-controlled content; script runs in the draw.io origin and can read or modify origin-accessible data.

CVSS severity6.1
Medium
EPSS probability0.40%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Reflected XSS in draw.io before 21.6.3 allows remote attackers to execute script in a victim's browser through crafted diagram content. The label-rendering path accepts HTML markup in diagram labels without passing it through the added DOMPurify sanitization. Exploitation requires a victim to open attacker-controlled content; script runs in the draw.io origin and can read or modify origin-accessible data.

The record

CVE
CVE-2023-3973
Published
Jul 27, 2023
Updated
Oct 15, 2024
Vendor
draw.io Ltd
Product
draw.io
Classifications
CWE-79, T1204.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 27, 2023CVE publishedPublication date reported by the CVE source.
  2. Oct 15, 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=0 <21.6.3
  2. Affected versionversion=unspecified <21.6.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

draw.io Ltd · draw.ioversion=0 <21.6.3; version=unspecified <21.6.3

Published CVSS scores

6.1NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
9.6huntr.devCVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:L

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')
T1204.001Malicious Link

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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