CVE-2022-4820Network attack vector

Script execution via unsanitized PHP_SELF form action

Published Dec 28, 2022 · Updated Aug 3, 2024

Cross-site scripting in the FlatPress Admin Area allows remote attackers to execute script in an administrator’s browser. The entry-list template inserts PHP_SELF directly into the form action, allowing markup in a crafted request path to enter the HTML response without sanitization. Exploitation requires an authenticated administrator to open the crafted Admin Area URL, and script runs in that user’s FlatPress origin.

CVSS severity6.1
Medium
EPSS probability0.52%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cross-site scripting in the FlatPress Admin Area allows remote attackers to execute script in an administrator’s browser. The entry-list template inserts PHP_SELF directly into the form action, allowing markup in a crafted request path to enter the HTML response without sanitization. Exploitation requires an authenticated administrator to open the crafted Admin Area URL, and script runs in that user’s FlatPress origin.

The record

CVE
CVE-2022-4820
Published
Dec 28, 2022
Updated
Aug 3, 2024
Vendor
FlatPress
Product
FlatPress
Classifications
CWE-79, T1204.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 28, 2022CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record 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=n/a

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

FlatPress · FlatPressversion=n/a

Published CVSS scores

6.1NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
3.5VulDBCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/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')
T1204.001Malicious 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

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Your stack

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