CVE-2021-25983Network attack vector

Session-cookie theft via unescaped forum filters

Published Nov 16, 2021 · Updated Apr 30, 2025

Reflected XSS in Darwin Factor's forum plugin 1.3.8 through 1.8.30 allows remote attackers to steal session cookies via crafted URLs. The topic-list.vue template inserts tags and category route-query values into raw HTML bindings without output encoding. Exploitation requires a victim to open a crafted forum URL, after which attacker-supplied JavaScript runs in that victim's browser session.

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

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Reflected XSS in Darwin Factor's forum plugin 1.3.8 through 1.8.30 allows remote attackers to steal session cookies via crafted URLs. The topic-list.vue template inserts tags and category route-query values into raw HTML bindings without output encoding. Exploitation requires a victim to open a crafted forum URL, after which attacker-supplied JavaScript runs in that victim's browser session.

The record

CVE
CVE-2021-25983
Published
Nov 16, 2021
Updated
Apr 30, 2025
Vendor
Darwin
Product
Factor
Classifications
CWE-79, T1204.001
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

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=1.3.8 <unspecified
  2. Affected versionversion=unspecified <=1.8.30

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Darwin · Factorversion=1.3.8 <unspecified; version=unspecified <=1.8.30

Published CVSS scores

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')
T1204.001User Execution: Malicious 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

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo