{"answers":{"affected":"2 open source packages ship an affected version, including msgpack5.","exploited":"There is no known exploitation of CVE-2026-107299 in the wild and no public exploit code.","fix":"Upgrade msgpack5 to 6.1.0 or later.","what":"CVE-2026-107299 is a medium-severity denial of service vulnerability in mcollina msgpack5, published on 8 Oct 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-2026-107299 and fix it if it is affected.\n\nWhat it is: CVE-2026-107299 is a medium-severity denial of service vulnerability in mcollina msgpack5, published on 8 Oct 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-2026-107299 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- msgpack5 (npm): affected all versions; fixed in 6.1.0\n- msgpack5 (npm): affected all versions; fixed in 6.1.0\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-2026-107299/ (Markdown: https://insights.sbomify.com/CVE-2026-107299/index.md)","id":"CVE-2026-107299","markdown":"https://insights.sbomify.com/CVE-2026-107299/index.md","name":"CVE-2026-107299","record":{"aliases":["AZL-106848","GHSA-26wq-p25c-j6fv"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"Node.js msgpack library","requires_auth":"none","summary":"A remote attacker can exhaust memory in msgpack5 by sending a reserved byte, causing a denial of service.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[],"cvss":{"score":5.9,"severity":"medium","source":"cna","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},"cwes":[{"id":"CWE-228","name":"Improper Handling of Syntactically Invalid Structure"}],"description":"msgpack5 is a msgpack v5 implementation for node.js and the browser. Prior to 6.1.0, the streaming decoder treats the reserved MessagePack byte 0xc1 as incomplete input instead of invalid input. When 0xc1 begins a stream, subsequent data remains buffered while the decoder waits for bytes that cannot make the value valid, allowing a remote peer to exhaust memory. This issue is fixed in version 6.1.0.","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":"msgpack5: Reserved byte can cause unbounded stream buffering","id":"CVE-2026-107299","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"npm","product":null,"products":[],"type":"denial_of_service","year":"2026"},"n_packages":2,"n_references":3,"next":{"headline":"msgpack5: Many buffered values can exhaust the streaming decoder stack","id":"CVE-2026-107300"},"packages":[{"ecosystem":"npm","fixed":["6.1.0"],"introduced":["0"],"last_affected":[],"package":"msgpack5","purl":null,"source":"GHSA-26wq-p25c-j6fv"},{"ecosystem":"npm","fixed":["6.1.0"],"introduced":["0"],"last_affected":[],"package":"msgpack5","purl":"pkg:npm/msgpack5","source":"GHSA-26wq-p25c-j6fv"}],"prev":{"headline":"msgpack5: Deeply nested input can exhaust the decoder stack","id":"CVE-2026-107298"},"products":["msgpack5"],"published":"2026-10-08","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":"no","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-10-09","vendors":["mcollina"]},"summary":"A remote attacker can exhaust memory in msgpack5 by sending a reserved byte, causing a denial of service.","url":"https://insights.sbomify.com/CVE-2026-107299/"}