{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2021-20235 in the wild and no public exploit code.","fix":"Upgrade to a fixed version.","what":"CVE-2021-20235 is a high-severity memory corruption vulnerability in zeromq, published on 1 Apr 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-2021-20235 and fix it if it is affected.\n\nWhat it is: CVE-2021-20235 is a high-severity memory corruption vulnerability in zeromq, published on 1 Apr 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-2021-20235 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-2021-20235/ (Markdown: https://insights.sbomify.com/CVE-2021-20235/index.md)","id":"CVE-2021-20235","markdown":"https://insights.sbomify.com/CVE-2021-20235/index.md","name":"CVE-2021-20235","record":{"aliases":["DEBIAN-CVE-2021-20235","GHSA-fc3w-qxf5-7hp6","GHSA-hrfc-mjc4-cv8f","JLSEC-2026-515","UBUNTU-CVE-2021-20235"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["code_execution","denial_of_service"],"network_reachable":"yes","non_default_config":true,"product_category":"ZeroMQ messaging library","requires_auth":"none","summary":"A remote attacker can trigger a buffer overflow in ZeroMQ via crafted requests if authentication is disabled, potentially leading to code execution or denial of service.","user_interaction":"not_required","vuln_class":"memory_corruption"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"redhat","cpe":[{"product":"libzmq","vendor":"zeromq"}],"cvss":{"score":8.1,"severity":"high","source":"nvd","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","version":"3.1"},"cwes":[{"id":"CWE-787","name":"Out-of-bounds Write"},{"id":"CWE-120","name":"Buffer Copy without Checking Size of Input"}],"description":"There's a flaw in the zeromq server in versions before 4.3.3 in src/decoder_allocators.hpp. The decoder static allocator could have its sized changed, but the buffer would remain the same as it is a static buffer. A remote, unauthenticated attacker who sends a crafted request to the zeromq server could trigger a buffer overflow WRITE of arbitrary data if CURVE/ZAP authentication is not enabled. The greatest impact of this flaw is to application availability, data integrity, and confidentiality.","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":"Memory corruption in zeromq","id":"CVE-2021-20235","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"memory_corruption","year":"2021"},"n_packages":0,"n_references":2,"next":{"headline":"Memory corruption in zeromq","id":"CVE-2021-20236"},"packages":[],"prev":{"headline":"Denial of service in zeromq","id":"CVE-2021-20234"},"products":["zeromq"],"published":"2021-04-01","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":7.5,"headline":"Denial of service in zeromq","id":"CVE-2021-20237","kev_date_added":null,"published":"2021-05-28"},{"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":"A remote attacker can trigger a buffer overflow in ZeroMQ via crafted requests if authentication is disabled, potentially leading to code execution or denial of service.","url":"https://insights.sbomify.com/CVE-2021-20235/"}