{"answers":{"affected":"It affects 3 products.","exploited":"There is no known exploitation of CVE-2018-20021 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2018-20021 is a high-severity denial of service vulnerability in Canonical Ubuntu Linux, published on 19 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-2018-20021 and fix it if it is affected.\n\nWhat it is: CVE-2018-20021 is a high-severity denial of service vulnerability in Canonical Ubuntu Linux, published on 19 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-2018-20021 in the wild and no public exploit code.\n\nAffected product: Canonical Ubuntu Linux. 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-2018-20021/ (Markdown: https://insights.sbomify.com/CVE-2018-20021/index.md)","id":"CVE-2018-20021","markdown":"https://insights.sbomify.com/CVE-2018-20021/index.md","name":"CVE-2018-20021","record":{"aliases":["DEBIAN-CVE-2018-20021","GHSA-m4r6-9jrx-9hxw","UBUNTU-CVE-2018-20021"],"analysis":{"component_type":"library","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"VNC client library","requires_auth":"none","summary":"An attacker can cause excessive CPU and RAM consumption in LibVNC clients via an infinite loop, leading to denial of service.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Kaspersky","cpe":[{"product":"ubuntu_linux","vendor":"canonical"},{"product":"debian_linux","vendor":"debian"},{"product":"libvncserver","vendor":"libvnc_project"}],"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-835","name":"Loop with Unreachable Exit Condition"}],"description":"LibVNC before commit c3115350eb8bb635d0fdb4dbbb0d0541f38ed19c contains a CWE-835: Infinite loop vulnerability in VNC client code. Vulnerability allows attacker to consume excessive amount of resources like CPU and RAM","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 LibVNC","id":"CVE-2018-20021","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"canonical:ubuntu_linux","products":["canonical:ubuntu_linux","debian:debian_linux"],"type":"denial_of_service","year":"2018"},"n_packages":0,"n_references":12,"next":{"headline":"Information disclosure in LibVNC","id":"CVE-2018-20022"},"packages":[],"prev":{"headline":"Memory corruption in LibVNC","id":"CVE-2018-20020"},"products":["LibVNC"],"published":"2018-12-19","related":[{"cvss_score":9.8,"headline":"SaltStack Salt Authentication Bypass","id":"CVE-2020-11651","kev_date_added":"2021-11-03","published":"2020-04-30"},{"cvss_score":9.8,"headline":"OpenSMTPD Remote Code Execution","id":"CVE-2020-7247","kev_date_added":"2022-03-25","published":"2020-01-29"},{"cvss_score":9.8,"headline":"Exim Out-of-bounds Write","id":"CVE-2019-16928","kev_date_added":"2022-03-03","published":"2019-09-27"},{"cvss_score":9.8,"headline":"Exim Buffer Overflow","id":"CVE-2018-6789","kev_date_added":"2021-11-03","published":"2018-02-08"},{"cvss_score":9.8,"headline":"Oracle Java SE and Java SE Embedded Remote Code Execution","id":"CVE-2015-2590","kev_date_added":"2022-03-03","published":"2015-07-16"},{"cvss_score":9.8,"headline":"Oracle JRE Remote Code Execution","id":"CVE-2013-0422","kev_date_added":"2022-05-25","published":"2013-01-10"},{"cvss_score":9.8,"headline":"Oracle Java SE Runtime Environment (JRE) Arbitrary Code Execution","id":"CVE-2011-3544","kev_date_added":"2022-03-03","published":"2011-10-19"}],"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":"2024-08-05","vendors":["n/a"]},"summary":"An attacker can cause excessive CPU and RAM consumption in LibVNC clients via an infinite loop, leading to denial of service.","url":"https://insights.sbomify.com/CVE-2018-20021/"}