PhpSpreadsheet allows unauthorized Reflected XSS in the constructor of the Downloader class

CVE-2024-56365 → View on GitHub ↗ View on CVE.org ↗ View on NVD ↗

Description

Unauthorized Reflected XSS in the constructor of the Downloader class

Product: Phpspreadsheet
Version: version 3.6.0
CWE-ID: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVSS vector v.3.1: 8.2 (AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:H/A:N)
CVSS vector v.4.0: 8.3 (AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:H/VA:N/SC:L/SI:H/SA:L)
Description: using the /vendor/phpoffice/phpspreadsheet/samples/download.php script, an attacker can perform a XSS-type attack
Impact: execution of arbitrary JavaScript code in the browser
Vulnerable component: the constructor of the Downloader class
Exploitation conditions: an unauthorized user
Mitigation: sanitization of the name and type variables
Researcher: Aleksey Solovev (Positive Technologies)

Research

The researcher discovered zero-day vulnerability Unauthorized Reflected Cross-Site Scripting (XSS) (in the constructor of the Downloader class) in Phpspreadsheet.

The latest version (3.6.0) of the phpoffice/phpspreadsheet library was installed. The installation was carried out with the inclusion of examples.

Listing 1. Installing the phpoffice/phpspreadsheet library

$ composer require phpoffice/phpspreadsheet --prefer-source

The ./vendor/phpoffice/phpspreadsheet/samples/download.php file processes the GET parameters name and type.

fig1

Figure 1. The ./vendor/phpoffice/phpspreadsheet/samples/download.php file accepts GET parameters.

Consider the constructor of the Downloader class, where GET parameters are passed. Error is displayed without sanitization using GET parameters transmitted from the user.

fig2

Figure 2. Error is displayed without sanitization

When clicking on the following link, arbitrary JavaScript code will be executed.

Listing 2.

https://192.***.***.***/vendor/phpoffice/phpspreadsheet/samples/download.php?name=%3Cimg%20src=1%20onerror=alert()%3E&type=1

Demonstration of the execution of arbitrary JavaScript code.

<img width="537" alt="fig3" src="https://github.com/user-attachments/assets/745d6e21-396f-4357-8ff8-e856adf15fee" />

Figure 3. Executing arbitrary JavaScript code

Credit

This vulnerability was discovered by Aleksey Solovev (Positive Technologies)

Basic information

Type
reviewed
Severity
high
Advisory on GitHub
Open advisory ↗
Repository advisory
Open repository advisory ↗
Source code
Browse source ↗
Published (advisory)
2025-01-03 17:06:05 UTC
Updated
2025-03-06 18:21:36 UTC
GitHub reviewed
2025-01-03 17:06:05 UTC
NVD published
2025-01-03

EPSS Score

Score Percentile
0.67% 70.80%

CVSS Scores

Base score Version Severity Vector
7.1 3.1 —
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:H/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
8.3 4.0 —
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:H/VA:N/SC:L/SI:H/SA:L Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network.
Attack complexity (AC:L)
Exploitation conditions are straightforward and stable.
Attack requirements (AT:N)
No additional preconditions are required beyond normal reachability.
Privileges required (PR:N)
No privileges are required.
User interaction (UI:A)
User interaction is required in an active way.
Vulnerable system confidentiality impact (VC:N)
No confidentiality impact on the vulnerable system.
Vulnerable system integrity impact (VI:H)
High integrity impact on the vulnerable system.
Vulnerable system availability impact (VA:N)
No availability impact on the vulnerable system.
Subsequent system confidentiality impact (SC:L)
Limited confidentiality impact on subsequent systems.
Subsequent system integrity impact (SI:H)
High integrity impact on subsequent systems.
Subsequent system availability impact (SA:L)
Limited availability impact on subsequent systems.

Identifiers

Type Value
GHSA GHSA-jmpx-686v-c3wx ↗
CVE CVE-2024-56365 ↗

CWEs

CWE id Name
CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Affected packages (5)

Vulnerable version ranges and first patched releases as published by GitHub.

Ecosystem Package Vulnerable range First patched Vulnerable functions
composer phpoffice/phpspreadsheet >= 3.0.0, < 3.7.0 3.7.0 —
composer phpoffice/phpspreadsheet <= 1.29.6 1.29.7 —
composer phpoffice/phpspreadsheet >= 2.0.0, <= 2.1.5 2.1.6 —
composer phpoffice/phpspreadsheet >= 2.2.0, <= 2.3.4 2.3.5 —
composer phpoffice/phpexcel <= 1.8.2 — —

References

cvelogic Threat Intelligence