{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2021-20237 in the wild and no public exploit code.","fix":"Upgrade to a fixed version.","what":"CVE-2021-20237 is a high-severity denial of service vulnerability in zeromq, published on 28 May 2021. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2021-20237 and fix it if it is affected.\n\nWhat it is: CVE-2021-20237 is a high-severity denial of service vulnerability in zeromq, published on 28 May 2021. 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-2021-20237 in the wild and no public exploit code.\n\nAffected product: zeromq. 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-2021-20237/ (Markdown: https://insights.sbomify.com/CVE-2021-20237/index.md)","id":"CVE-2021-20237","markdown":"https://insights.sbomify.com/CVE-2021-20237/index.md","name":"CVE-2021-20237","record":{"aliases":["DEBIAN-CVE-2021-20237","GHSA-4p5v-h92w-6wxw","GHSA-98wx-fq4r-jfm2","JLSEC-2026-517","UBUNTU-CVE-2021-20237"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":true,"product_category":"ZeroMQ messaging library","requires_auth":"none","summary":"Remote attackers can cause denial of service via memory exhaustion in ZeroMQ when authentication is disabled.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"redhat","cpe":[{"product":"libzmq","vendor":"zeromq"}],"cvss":{"score":7.5,"severity":"high","source":"nvd","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-401","name":"Missing Release of Memory after Effective Lifetime"},{"id":"CWE-400","name":"Uncontrolled Resource Consumption"}],"description":"An uncontrolled resource consumption (memory leak) flaw was found in ZeroMQ's src/xpub.cpp in versions before 4.3.3. This flaw allows a remote unauthenticated attacker to send crafted PUB messages that consume excessive memory if the CURVE/ZAP authentication is disabled on the server, causing a denial of service. The highest threat from this vulnerability is to system availability.","ecosystems":[],"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 zeromq","id":"CVE-2021-20237","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"denial_of_service","year":"2021"},"n_packages":0,"n_references":2,"next":{"headline":"Missing authorization in openshift/machine-config-operator","id":"CVE-2021-20238"},"packages":[],"prev":{"headline":"Memory corruption in zeromq","id":"CVE-2021-20236"},"products":["zeromq"],"published":"2021-05-28","related":[{"cvss_score":9.8,"headline":"Memory corruption in n/a","id":"CVE-2020-36400","kev_date_added":null,"published":"2021-07-01"},{"cvss_score":8.1,"headline":"Memory corruption in zeromq","id":"CVE-2021-20235","kev_date_added":null,"published":"2021-04-01"},{"cvss_score":6.5,"headline":"Denial of service in zeromq","id":"CVE-2021-20234","kev_date_added":null,"published":"2021-04-01"}],"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":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2024-08-03","vendors":["n/a"]},"summary":"Remote attackers can cause denial of service via memory exhaustion in ZeroMQ when authentication is disabled.","url":"https://insights.sbomify.com/CVE-2021-20237/"}