CVE-2021-25984Network attack vector

Session-cookie theft via unsanitized forum replies

Published Nov 16, 2021 · Updated Apr 30, 2025

Stored XSS in Darwin Factor 1.3.3 through 1.8.30 allows remote attackers to steal session cookies through forum replies. The topic-reply Vue component renders stored reply content as HTML without neutralizing attacker-controlled markup. The reply can be submitted without authentication, but script execution requires another user to view the affected forum thread; the reported consequence is session-cookie theft.

CVSS severity6.1
Medium
EPSS probability0.71%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored XSS in Darwin Factor 1.3.3 through 1.8.30 allows remote attackers to steal session cookies through forum replies. The topic-reply Vue component renders stored reply content as HTML without neutralizing attacker-controlled markup. The reply can be submitted without authentication, but script execution requires another user to view the affected forum thread; the reported consequence is session-cookie theft.

The record

CVE
CVE-2021-25984
Published
Nov 16, 2021
Updated
Apr 30, 2025
Vendor
Darwin
Product
Factor
Classifications
CWE-79, T1539
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Nov 16, 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=1.3.3 <unspecified
  2. Affected versionversion=unspecified <=1.8.30

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Darwin · Factorversion=1.3.3 <unspecified; version=unspecified <=1.8.30

Published CVSS scores

4.3NIST NVDAV:N/AC:M/Au:N/C:N/I:P/A:N
6.1MendCVSS: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')
T1539Steal Web Session Cookie

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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