SB20261109124 - Multiple vulnerabilities in OctoPrint

CSH
CYBERSECURITY HELP
Sign In REGISTER

Main Vulnerability Database SB20261109124

SB20261109124 - Multiple vulnerabilities in OctoPrint

Published: November 9, 2026

Security Bulletin ID SB20261109124
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities 3
Exploitation vector Remote access
Highest impact Data manipulation

Breakdown by Severity

Medium 33% Low 67%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 3 vulnerabilities.


1) External Control of File Name or Path (CVE-ID: CVE-2026-54134)

CWE-ID: CWE-73 - External Control of File Name or Path

CVSSv4: 7 [CVSS:4.0/AV:A/AC:L/AT:N/PR:L/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows an authenticated adjacent-network attacker with FILE_UPLOAD permission to exfiltrate host files readable by OctoPrint, including configuration secrets.

The vulnerability exists due to incomplete validation of reserved file-path parameters in OctoPrint's upload endpoints when processing query parameters or inconsistently parsed requests. An authenticated adjacent-network attacker with FILE_UPLOAD permission can inject these parameters to make OctoPrint treat a host file as an upload and move it into the upload folder for downloading.


2) Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS) (CVE-ID: CVE-2026-35163)

CWE-ID: CWE-80 - Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS)

CVSSv4: 5.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N]


The vulnerability allows an unauthenticated attacker to execute arbitrary JavaScript in an OctoPrint user's browser.

The vulnerability exists due to improper neutralization of HTML in printer-generated Suppressed Command notification popups triggered by a specially crafted print file when notifications are enabled. An unauthenticated attacker can convince a victim to print the file and then disrupt ongoing prints or extract sensitive configuration settings if the victim has permission to access them.


3) Cross-site scripting (CVE-ID: CVE-2026-123364)

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

CVSSv4: 2.4 [CVSS:4.0/AV:A/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N]


The vulnerability allows a low-privileged adjacent-network attacker to execute JavaScript in another user's browser through stored cross-site scripting.

The vulnerability exists due to improper neutralization of saved port or baudrate defaults in OctoPrint's bundled Serial Connector plugin when supplied through an API connection request. A low-privileged adjacent-network attacker can submit crafted connection defaults that execute when a victim views the affected interface.


Remediation

Install update from vendor's website.

References