{"answers":{"affected":"2 open source packages ship an affected version, including h3.","exploited":"There is no known exploitation of CVE-2026-86250 in the wild and no public exploit code.","fix":"Upgrade h3 to 2.0.1-rc.18 or later.","what":"CVE-2026-86250 is a high-severity denial of service vulnerability in h3js h3, published on 6 Sep 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-2026-86250 and fix it if it is affected.\n\nWhat it is: CVE-2026-86250 is a high-severity denial of service vulnerability in h3js h3, published on 6 Sep 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-2026-86250 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- h3 (npm): affected from 2.0.0-beta.4; fixed in 2.0.1-rc.18\n- h3 (npm): affected from 2.0.0-beta.4; fixed in 2.0.1-rc.18\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-2026-86250/ (Markdown: https://insights.sbomify.com/CVE-2026-86250/index.md)","id":"CVE-2026-86250","markdown":"https://insights.sbomify.com/CVE-2026-86250/index.md","name":"CVE-2026-86250","record":{"aliases":["GHSA-q5pr-72pq-83v3"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"Node.js HTTP library","requires_auth":"none","summary":"Attackers can cause a denial of service by sending crafted cookies with large chunk counts, hanging the server process in the h3 library.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"VulnCheck","cpe":[],"cvss":{"score":8.7,"severity":"high","source":"cna","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","version":"4.0"},"cwes":[{"id":"CWE-400","name":"Uncontrolled Resource Consumption"}],"description":"h3 versions before 2.0.1-rc.18 fail to validate the chunk count parsed from user-controlled cookie values in setChunkedCookie() and deleteChunkedCookie() functions. Attackers can send a crafted cookie header with an extremely large chunk count to trigger an O(n²) cleanup loop that hangs the server process.","ecosystems":["npm"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":true,"headline":"h3 before 2.0.1-rc.18 Denial of Service via Unbounded Chunked Cookie","id":"CVE-2026-86250","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"npm","product":null,"products":[],"type":"denial_of_service","year":"2026"},"n_packages":2,"n_references":2,"next":{"headline":"h3 before 1.15.9 Path Traversal via Double Decoding","id":"CVE-2026-86251"},"packages":[{"ecosystem":"npm","fixed":["2.0.1-rc.18"],"introduced":["2.0.0-beta.4"],"last_affected":[],"package":"h3","purl":null,"source":"GHSA-q5pr-72pq-83v3"},{"ecosystem":"npm","fixed":["2.0.1-rc.18"],"introduced":["2.0.0-beta.4"],"last_affected":[],"package":"h3","purl":"pkg:npm/h3","source":"GHSA-q5pr-72pq-83v3"}],"prev":{"headline":"Apache bRPC: Authentication bypass when a server sets ServerOptions.internal_port and ServerOptions.auth","id":"CVE-2026-86249"},"products":["h3"],"published":"2026-09-06","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"GitHub Advisory Database","prefix":"GHSA"},{"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":"2026-09-18","vendors":["h3js"]},"summary":"Attackers can cause a denial of service by sending crafted cookies with large chunk counts, hanging the server process in the h3 library.","url":"https://insights.sbomify.com/CVE-2026-86250/"}