OctoPrint Vulnerable to Denial of Service through malformed HTTP request in OctoPrint

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

6.5 · CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS

• CVE-2025-48879: 0.26% estimated exploitation activity in the next 30 days; percentile 17.30 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Impact OctoPrint versions up until and including 1.11.1 contain a vulnerability that allows any unauthenticated attacker to send a manipulated broken multipart/form-data request to OctoPrint and through that make the web server component become unresponsive. This could be used to effectively run a denial of service attack on the OctoPrint server. Patches The vulnerability has been patched in version 1.11.2. Workaround OctoPrint administrators are once more reminded to not make OctoPrint available on hostile networks (e.g. the internet), regardless of whether this vulnerability is patched or not. Details The issue can be triggered by a broken multipart/form-data request lacking an end boundary to any of OctoPrint's endpoints implemented through the octoprint.server.util.tornado.UploadStorageFallbackHandler request handler. The request handler will get stuck in an endless busy loop, looking for a part of the request that will never come. As Tornado is single-threaded, that will…

Published by the source

10 Jun 2025, 20:14 UTC

Last modified by the source

7 Jul 2026, 17:57 UTC

Source last checked

26 Oct 2026, 13:32 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-9wj4-8h85-pgrw

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-9wj4-8h85-pgrw

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# Patch Next advisory brief: CVE-2025-48879

Advisory: OctoPrint Vulnerable to Denial of Service through malformed HTTP request in OctoPrint
IDs: CVE-2025-48879, GHSA-9wj4-8h85-pgrw
Record: https://patchnext.com/advisories/cve-2025-48879 (revision 2, source checked 26 Oct 2026, 13:32 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 6.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: octoprint 1.11.2. A vendor fix does not mean a deployment is fixed.

## Affected components
- PyPI octoprint: affected < 1.11.2; fixed in 1.11.2

## Suggested inspection (read-only)
- `python -m pip show octoprint`: prints the installed version. Run with the environment that serves production active.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on octoprint.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-9wj4-8h85-pgrw (OSV record GHSA-9wj4-8h85-pgrw lists affected ranges: PyPI octoprint >=0 <1.11.2 (fixed))
- Verified: https://github.com/advisories/GHSA-9wj4-8h85-pgrw (GitHub-reviewed advisory GHSA-9wj4-8h85-pgrw lists affected ranges: PyPI octoprint >=0 <1.11.2)

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