CVE-2021-38331Network attack vector

Browser script execution via unencoded posted parameter

Published Sep 10, 2021 · Updated May 2, 2025

Reflected XSS in WP-T-Wap 1.13.2 and earlier allows remote attackers to inject scripts through the posted parameter in wap/writer.php. The handler reflects the untrusted posted value into its HTML response without output encoding, so the browser interprets injected markup as active content. Execution requires a victim to interact with the crafted request and occurs in the affected site's browser origin, enabling page-content access or modification.

CVSS severity6.1
Medium
EPSS probability0.90%
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 WP-T-Wap 1.13.2 and earlier allows remote attackers to inject scripts through the posted parameter in wap/writer.php. The handler reflects the untrusted posted value into its HTML response without output encoding, so the browser interprets injected markup as active content. Execution requires a victim to interact with the crafted request and occurs in the affected site's browser origin, enabling page-content access or modification.

The record

CVE
CVE-2021-38331
Published
Sep 10, 2021
Updated
May 2, 2025
Vendor
WP-T-Wap Project
Product
WP-T-Wap
Classifications
CWE-79
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 10, 2021CVE publishedPublication date reported by the CVE source.
  2. May 2, 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=1.13.2 <=1.13.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

WP-T-Wap Project · WP-T-Wapversion=1.13.2 <=1.13.2

Published CVSS scores

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.

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')

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