{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2018-20421 in the wild and no public exploit code.","fix":"No fix has been published for CVE-2018-20421 yet. Limit exposure of the affected software until one is available.","what":"CVE-2018-20421 is a high-severity denial of service vulnerability in n/a, published on 24 Dec 2018. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2018-20421 and fix it if it is affected.\n\nWhat it is: CVE-2018-20421 is a high-severity denial of service vulnerability in n/a, published on 24 Dec 2018. 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-2018-20421 in the wild and no public exploit code.\n\nAffected product: n/a. 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-2018-20421/ (Markdown: https://insights.sbomify.com/CVE-2018-20421/index.md)","id":"CVE-2018-20421","markdown":"https://insights.sbomify.com/CVE-2018-20421/index.md","name":"CVE-2018-20421","record":{"aliases":["GHSA-5g4w-3m99-4m2p"],"analysis":{"component_type":"other","fix_type":"upgrade","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"Ethereum client","requires_auth":"none","summary":"Attackers can cause denial of service in Go Ethereum by manipulating dynamic array lengths and writing to large memory indices.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"mitre","cpe":[{"product":"go_ethereum","vendor":"ethereum"}],"cvss":{"score":7.5,"severity":"high","source":"nvd","vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.0"},"cwes":[{"id":"CWE-770","name":"Allocation of Resources Without Limits or Throttling"}],"description":"Go Ethereum (aka geth) 1.8.19 allows attackers to cause a denial of service (memory consumption) by rewriting the length of a dynamic array in memory, and then writing data to a single memory location with a large index number, as demonstrated by use of \"assembly { mstore }\" followed by a \"c[0xC800000] = 0xFF\" assignment.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":false,"headline":"Denial of service in n/a","id":"CVE-2018-20421","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"denial_of_service","year":"2018"},"n_packages":0,"n_references":1,"next":{"headline":"Auth bypass in n/a","id":"CVE-2018-20422"},"packages":[],"prev":{"headline":"Path traversal in n/a","id":"CVE-2018-20420"},"products":["n/a"],"published":"2018-12-24","related":[{"cvss_score":8.7,"headline":"Go Ethereum affected by DoS via malicious p2p message","id":"CVE-2026-26314","kev_date_added":null,"published":"2026-02-19"},{"cvss_score":7.5,"headline":"go-ethereum vulnerable to denial of service via crafted GraphQL query","id":"CVE-2023-42319","kev_date_added":null,"published":"2023-10-18"},{"cvss_score":7.5,"headline":"Denial of service via malicious p2p message in go-ethereum","id":"CVE-2023-40591","kev_date_added":null,"published":"2023-09-06"},{"cvss_score":7.5,"headline":"Denial of service in go-ethereum","id":"CVE-2021-42219","kev_date_added":null,"published":"2022-03-16"},{"cvss_score":7.5,"headline":"Denial of Service in Go-Ethereum","id":"CVE-2022-23327","kev_date_added":null,"published":"2022-03-04"},{"cvss_score":7.5,"headline":"Denial of Service in Go-Ethereum","id":"CVE-2022-23328","kev_date_added":null,"published":"2022-03-04"}],"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":"2024-09-17","vendors":["n/a"]},"summary":"Attackers can cause denial of service in Go Ethereum by manipulating dynamic array lengths and writing to large memory indices.","url":"https://insights.sbomify.com/CVE-2018-20421/"}