{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-18549 in the wild and no public exploit code.","fix":"No fix has been published for CVE-2026-18549 yet. Limit exposure of the affected software until one is available.","what":"CVE-2026-18549 is a high-severity denial of service vulnerability in @fastify/multipart, published on 15 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-18549 and fix it if it is affected.\n\nWhat it is: CVE-2026-18549 is a high-severity denial of service vulnerability in @fastify/multipart, published on 15 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2026-18549 in the wild and no public exploit code.\n\nAffected product: @fastify/multipart. No package-level version data is available, so check the vendor advisory linked from the reference page.\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2026-18549/ (Markdown: https://insights.sbomify.com/CVE-2026-18549/index.md)","id":"CVE-2026-18549","markdown":"https://insights.sbomify.com/CVE-2026-18549/index.md","name":"CVE-2026-18549","record":{"aliases":["GHSA-vmph-573x-85f6"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"Fastify multipart parser","requires_auth":"none","summary":"An unauthenticated attacker can cause disk and event-loop exhaustion by aborting uploads after the file size limit is reached, hanging request handlers.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"openjs","cpe":[{"product":"fastify-multipart","vendor":"fastify"}],"cvss":{"score":7.5,"severity":"high","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},"cwes":[{"id":"CWE-664","name":"Improper Control of a Resource Through its Lifetime"},{"id":"CWE-400","name":"Uncontrolled Resource Consumption"}],"description":"@fastify/multipart is a multipart form-data parser for Fastify. In versions from 5.3.0 up to but not including 10.1.1, when the busboy fileSize limit truncates a file part, the plugin clears its internal current-file reference while the underlying stream is still open. If the client then aborts the connection before sending the terminating boundary, the abort cleanup finds no stream to destroy, so saveRequestFiles() never settles, the request handler hangs, and the temporary file already written to disk is never cleaned up. An unauthenticated client can repeat this to permanently leak temporary files and suspended handler executions, leading to disk and event-loop exhaustion. The issue is fixed in @fastify/multipart 10.1.1. Users should upgrade to 10.1.1.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":false,"headline":"@fastify/multipart vulnerable to Denial of Service via aborted upload after fileSize limit","id":"CVE-2026-18549","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"denial_of_service","year":"2026"},"n_packages":0,"n_references":2,"next":{"headline":"Nokri - Job Board WordPress Theme \u003c= 1.6.6 - Unauthenticated Privilege Escalation via 'token' Parameter","id":"CVE-2026-18550"},"packages":[],"prev":{"headline":"Groundhogg \u003c= 4.5.14 - Unauthenticated Stored Cross-Site Scripting via 'ref' Parameter","id":"CVE-2026-18548"},"products":["@fastify/multipart"],"published":"2026-08-15","related":[{"cvss_score":7.5,"headline":"@fastify/multipart vulnerable to Denial of Service via temporary file leak on aborted upload","id":"CVE-2026-19474","kev_date_added":null,"published":"2026-08-15"},{"cvss_score":7.5,"headline":"@fastify/multipart vulnerable to DoS due to unlimited number of parts","id":"CVE-2023-25576","kev_date_added":null,"published":"2023-02-14"},{"cvss_score":7.5,"headline":"Denial of Service (DoS)","id":"CVE-2021-23597","kev_date_added":null,"published":"2022-02-11"},{"cvss_score":7.5,"headline":"Uncontrolled Resource Consumption in fastify-multipart","id":"CVE-2020-8136","kev_date_added":null,"published":"2020-03-20"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"US public information, NVD API terms","name":"NVD"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"yes","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-08-17","vendors":["@fastify/multipart"]},"summary":"An unauthenticated attacker can cause disk and event-loop exhaustion by aborting uploads after the file size limit is reached, hanging request handlers.","url":"https://insights.sbomify.com/CVE-2026-18549/"}