{"id":"CVE-2025-48879","aliases":["GHSA-9wj4-8h85-pgrw","PYSEC-2026-1713"],"url":"https://o3.security/vulnerability/CVE-2025-48879","summary":"OctoPrint Vulnerable to Denial of Service through malformed HTTP request","details":"### Impact\n\nOctoPrint 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.\n\n### Patches\n\nThe vulnerability has been patched in version 1.11.2.\n\n### Workaround\n\nOctoPrint 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.\n\n### Details\n\nThe 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 effectively block the whole web server.\n\nThe fix adds detection of invalid requests like that and ensures they are handled gracefully with an HTTP 400 Bad Request response.\n\n### Credits\n\nThis vulnerability was discovered and responsibly disclosed to OctoPrint by Jacopo Tediosi.","published":"2025-06-10T15:23:54.150Z","modified":"2026-08-27T03:31:07.102328007Z","cvss":{"score":6.5,"severity":"MEDIUM","vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},"epss":{"score":0.00223,"percentile":0.12643,"asOf":"2026-08-24"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"PyPI","name":"octoprint","fixedVersion":"1.11.2"}],"fix":{"url":"https://github.com/OctoPrint/OctoPrint/commit/c9c35c17bd820f19c6b12e6c0359fc0cfdd0c1ec","label":"OctoPrint/OctoPrint@c9c35c1"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/48xxx/CVE-2025-48879.json"},{"type":"ADVISORY","url":"https://github.com/OctoPrint/OctoPrint/security/advisories/GHSA-9wj4-8h85-pgrw"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-48879"},{"type":"FIX","url":"https://github.com/OctoPrint/OctoPrint/commit/c9c35c17bd820f19c6b12e6c0359fc0cfdd0c1ec"},{"type":"PACKAGE","url":"https://github.com/OctoPrint/OctoPrint"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-27T03:31:07.102328007Z"}}