CVE-2026-35163

Session script execution via unescaped notifications

Published Aug 21, 2026 · Updated Aug 21, 2026

Cross-site scripting in OctoPrint before 1.11.8 and 2.0.0rc1 through 2.0.0rc2 allows attackers to run script in a victim's session. The Suppressed Command handler in terminal.js passes printer-controlled payload.command and payload.message values to PNotify as HTML without escaping them. A victim must print a crafted file and view the resulting popup; injected script can disrupt the print, read settings allowed to that victim, and act with the victim's OctoPrint permissions.

CVSS severity4.6
Medium
EPSS probability0.14%
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 OctoPrint before 1.11.8 and 2.0.0rc1 through 2.0.0rc2 allows attackers to run script in a victim's session. The Suppressed Command handler in terminal.js passes printer-controlled payload.command and payload.message values to PNotify as HTML without escaping them. A victim must print a crafted file and view the resulting popup; injected script can disrupt the print, read settings allowed to that victim, and act with the victim's OctoPrint permissions.

The record

CVE
CVE-2026-35163
Published
Aug 21, 2026
Updated
Aug 21, 2026
Vendor
OctoPrint
Product
OctoPrint
Classifications
CWE-80, T1203
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 21, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 21, 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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 1.11.8
  2. Affected versionversion=>= 2.0.0rc1, < 2.0.0rc3

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

OctoPrint · OctoPrintversion=< 1.11.8; version=>= 2.0.0rc1, < 2.0.0rc3

Published CVSS scores

4.6GitHub Maintainer AdvisoryCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:L/SC:L/SI:L/SA: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)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

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