CVE-2021-25993Network attack vector

Account takeover via unsanitized SVG upload

Published Dec 29, 2021 · Updated Apr 30, 2025

Stored cross-site scripting in Wiki.js 2.0.0-beta.147 through 2.5.255 allows remote authenticated users to steal JWT tokens via SVG uploads. The asset upload path stores SVG content without sanitizing embedded JavaScript, which executes when another user views the file directly. Exploitation requires editor-level upload permission and victim interaction, enabling account takeover through token theft.

CVSS severity5.4
Medium
EPSS probability0.62%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored cross-site scripting in Wiki.js 2.0.0-beta.147 through 2.5.255 allows remote authenticated users to steal JWT tokens via SVG uploads. The asset upload path stores SVG content without sanitizing embedded JavaScript, which executes when another user views the file directly. Exploitation requires editor-level upload permission and victim interaction, enabling account takeover through token theft.

The record

CVE
CVE-2021-25993
Published
Dec 29, 2021
Updated
Apr 30, 2025
Vendor
Requarks.io
Product
Wiki.js
Classifications
CWE-79, T1189
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Dec 29, 2021CVE publishedPublication date reported by the CVE source.
  2. Apr 30, 2025Record 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=2.0.0-beta.147 <unspecified
  2. Affected versionversion=unspecified <=2.5.255

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Requarks.io · Wiki.jsversion=2.0.0-beta.147 <unspecified; version=unspecified <=2.5.255

Published CVSS scores

5.4NISTCVSS:3.1/AV:N/AC:L/PR:L/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
Privilegesauthenticated
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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