{"answers":{"affected":"2 open source packages ship an affected version, including node and node-min. It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-21637 in the wild and no public exploit code.","fix":"Upgrade node to a fixed version for your release line: 20.20.0, 22.22.0, 24.13.0 or 25.3.0.","what":"CVE-2026-21637 is a medium-severity denial of service vulnerability in Nodejs Node.js, published on 20 Jan 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-2026-21637 and fix it if it is affected.\n\nWhat it is: CVE-2026-21637 is a medium-severity denial of service vulnerability in Nodejs Node.js, published on 20 Jan 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-2026-21637 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- node (Bitnami): affected all versions; fixed in 20.20.0, 22.22.0, 24.13.0, 25.3.0\n- node-min (Bitnami): affected all versions; fixed in 20.20.0, 22.22.0, 24.13.0, 25.3.0\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-2026-21637/ (Markdown: https://insights.sbomify.com/CVE-2026-21637/index.md)","id":"CVE-2026-21637","markdown":"https://insights.sbomify.com/CVE-2026-21637/index.md","name":"CVE-2026-21637","record":{"aliases":["ALPINE-CVE-2026-21637","AZL-75080","BELL-CVE-2026-21637","BIT-node-2026-21637","BIT-node-min-2026-21637","CLEANSTART-2026-ND53075","CLEANSTART-2026-NF20161","CLSA-2026-1770993656","CLSA-2026-1771236630","DEBIAN-CVE-2026-21637","GHSA-ggxc-26fx-987r","MINI-3629-3xf2-wh6c","MINI-59w5-5xcp-wr74","MINI-fjq4-w2ww-jc3c","MINI-h2mw-mgv7-2cx5","MINI-hv7x-3mxw-6v25","MINI-pprm-cmmh-v6xg","MINI-rhcf-8p93-mxff","UBUNTU-CVE-2026-21637"],"analysis":{"component_type":"library","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":true,"product_category":"Node.js runtime","requires_auth":"none","summary":"Remote attackers can crash Node.js TLS servers or exhaust resources by triggering unhandled exceptions in PSK or ALPN callbacks during the handshake.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"hackerone","cpe":[{"product":"node.js","vendor":"nodejs"}],"cvss":{"score":5.9,"severity":"medium","source":"cna","vector":"CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.0"},"cwes":[{"id":"CWE-400","name":"Uncontrolled Resource Consumption"}],"description":"A flaw in Node.js TLS error handling allows remote attackers to crash or exhaust resources of a TLS server when `pskCallback` or `ALPNCallback` are in use. Synchronous exceptions thrown during these callbacks bypass standard TLS error handling paths (tlsClientError and error), causing either immediate process termination or silent file descriptor leaks that eventually lead to denial of service. Because these callbacks process attacker-controlled input during the TLS handshake, a remote client can repeatedly trigger the issue. This vulnerability affects TLS servers using PSK or ALPN callbacks across Node.js versions where these callbacks throw without being safely wrapped.","ecosystems":["Bitnami"],"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":"Denial of service in node","id":"CVE-2026-21637","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"Bitnami","product":"nodejs:node.js","products":["nodejs:node.js"],"type":"denial_of_service","year":"2026"},"n_packages":2,"n_references":1,"next":{"headline":"Command injection in UBB","id":"CVE-2026-21638"},"packages":[{"ecosystem":"Bitnami","fixed":["20.20.0","22.22.0","24.13.0","25.3.0"],"introduced":["0","21.0.0","23.0.0","25.0.0"],"last_affected":[],"package":"node","purl":"pkg:bitnami/node","source":"BIT-node-2026-21637"},{"ecosystem":"Bitnami","fixed":["20.20.0","22.22.0","24.13.0","25.3.0"],"introduced":["0","21.0.0","23.0.0","25.0.0"],"last_affected":[],"package":"node-min","purl":"pkg:bitnami/node-min","source":"BIT-node-min-2026-21637"}],"prev":{"headline":"Security feature bypass in node","id":"CVE-2026-21636"},"products":["node"],"published":"2026-01-20","related":[{"cvss_score":9.8,"headline":"Security feature bypass in Node","id":"CVE-2023-32002","kev_date_added":null,"published":"2023-08-21"},{"cvss_score":9.8,"headline":"Integer overflow in n/a","id":"CVE-2016-6303","kev_date_added":null,"published":"2016-09-16"},{"cvss_score":9.1,"headline":"Security feature bypass in Node.js","id":"CVE-2017-15896","kev_date_added":null,"published":"2017-12-11"},{"cvss_score":8.8,"headline":"Server-side request forgery in Node.js","id":"CVE-2018-7160","kev_date_added":null,"published":"2018-05-17"},{"cvss_score":8.1,"headline":"Misconfiguration in Node.js","id":"CVE-2018-12120","kev_date_added":null,"published":"2018-11-28"},{"cvss_score":7.9,"headline":"Path traversal in Node","id":"CVE-2024-21891","kev_date_added":null,"published":"2024-02-20"},{"cvss_score":7.9,"headline":"Path traversal in Node","id":"CVE-2024-21896","kev_date_added":null,"published":"2024-02-20"}],"sources":[{"class":"attribution","licence":"Apache-2.0","name":"Bitnami","prefix":"BIT"},{"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":"2026-01-21","vendors":["nodejs"]},"summary":"Remote attackers can crash Node.js TLS servers or exhaust resources by triggering unhandled exceptions in PSK or ALPN callbacks during the handshake.","url":"https://insights.sbomify.com/CVE-2026-21637/"}