CVE-2021-25977Network attack vector

Stored XSS via unescaped sitemap page titles

Published Oct 25, 2021 · Updated Apr 30, 2025

Stored XSS in Piranha CMS 7.0.0 through 9.1.1 allows remote authenticated users to execute JavaScript via a crafted page title. The Manager sitemap component passes item.title to Vue's v-html directive, causing stored title text to be interpreted as HTML instead of escaped text. Low-privileged page-creation access is required, and execution occurs when another Manager user views the affected sitemap entry.

CVSS severity5.4
Medium
EPSS probability0.65%
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 Piranha CMS 7.0.0 through 9.1.1 allows remote authenticated users to execute JavaScript via a crafted page title. The Manager sitemap component passes item.title to Vue's v-html directive, causing stored title text to be interpreted as HTML instead of escaped text. Low-privileged page-creation access is required, and execution occurs when another Manager user views the affected sitemap entry.

The record

CVE
CVE-2021-25977
Published
Oct 25, 2021
Updated
Apr 30, 2025
Vendor
Piranha CMS
Product
Piranha CMS
Classifications
CWE-79, T1059.007
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Oct 25, 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=7.0.0 <unspecified
  2. Affected versionversion=unspecified <=9.1.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Piranha CMS · Piranha CMSversion=7.0.0 <unspecified; version=unspecified <=9.1.1

Published CVSS scores

3.5NVDAV:N/AC:M/Au:S/C:N/I:P/A:N
5.4MendCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
5.4NVDCVSS: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')
T1059.007JavaScript/JScript

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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