CVE-2021-29051Network attack vector

Reflected XSS via unsanitized asset entry identifier

Published May 17, 2021 · Updated Jul 9, 2026

Reflected XSS in Liferay Portal 7.2.0 through 7.3.5 allows remote attackers to inject script via Asset Publisher requests. The Asset Publisher app reflects the assetEntryId parameter into page output without neutralizing HTML or script content; Liferay DXP 7.1 before fix pack 21, 7.2 before fix pack 10, and 7.3 before fix pack 1 is also affected. Exploitation requires a user to open an attacker-crafted request, allowing script to run in that user's browser context and read or alter page data available to the session.

CVSS severity6.1
Medium
EPSS probability0.75%
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 Liferay Portal 7.2.0 through 7.3.5 allows remote attackers to inject script via Asset Publisher requests. The Asset Publisher app reflects the assetEntryId parameter into page output without neutralizing HTML or script content; Liferay DXP 7.1 before fix pack 21, 7.2 before fix pack 10, and 7.3 before fix pack 1 is also affected. Exploitation requires a user to open an attacker-crafted request, allowing script to run in that user's browser context and read or alter page data available to the session.

The record

CVE
CVE-2021-29051
Published
May 17, 2021
Updated
Jul 9, 2026
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-79, T1203
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 17, 2021CVE publishedPublication date reported by the CVE source.
  2. Jul 9, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

4.3NVDAV:N/AC:M/Au:N/C:N/I:P/A:N
6.1NVDCVSS: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')
T1203Exploitation for Client Execution

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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