CVE-2021-34654Network attack vector

Browser script execution via unneutralized cptr name

Published Aug 16, 2021 · Updated May 5, 2025

Reflected XSS in Custom Post Type Relations 1.0 and earlier allows remote attackers to inject arbitrary web scripts via cptr[name]. pages/admin-page.php reflects the request value into an administrative page without neutralizing it for HTML output. The attacker needs no account, but an authenticated administrator must open the crafted request; the script then runs with that browser session's site privileges.

CVSS severity6.1
Medium
EPSS probability0.90%
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 Custom Post Type Relations 1.0 and earlier allows remote attackers to inject arbitrary web scripts via cptr[name]. pages/admin-page.php reflects the request value into an administrative page without neutralizing it for HTML output. The attacker needs no account, but an authenticated administrator must open the crafted request; the script then runs with that browser session's site privileges.

The record

CVE
CVE-2021-34654
Published
Aug 16, 2021
Updated
May 5, 2025
Vendor
Alex Jose
Product
Custom Post Type Relations
Classifications
CWE-79, T1203
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 16, 2021CVE publishedPublication date reported by the CVE source.
  2. May 5, 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=1.0 <=1.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Alex Jose · Custom Post Type Relationsversion=1.0 <=1.0

Published CVSS scores

6.1NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
4.3NIST NVDAV:N/AC:M/Au:N/C:N/I:P/A:N
6.1WordfenceCVSS: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.

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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')
T1203Exploitation for Client Execution

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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