{"answers":{"affected":"","exploited":"It is not confirmed as exploited in the wild, but public exploit code for CVE-2020-37134 exists.","fix":"No fix has been published for CVE-2020-37134 yet. Limit exposure of the affected software until one is available.","what":"CVE-2020-37134 is a medium-severity denial of service vulnerability in UltraVNC Viewer, published on 5 Feb 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link."},"fix_prompt":"Check this codebase for CVE-2020-37134 and fix it if it is affected.\n\nWhat it is: CVE-2020-37134 is a medium-severity denial of service vulnerability in UltraVNC Viewer, published on 5 Feb 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.\nExploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2020-37134 exists.\n\nAffected product: UltraVNC Viewer. 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-2020-37134/ (Markdown: https://insights.sbomify.com/CVE-2020-37134/index.md)","id":"CVE-2020-37134","markdown":"https://insights.sbomify.com/CVE-2020-37134/index.md","name":"CVE-2020-37134","record":{"aliases":["GHSA-w28g-7hwj-hqwj"],"analysis":{"component_type":"desktop_application","fix_type":"no_fix_stated","impacts":["denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"VNC client","requires_auth":"none","summary":"Attackers can crash UltraVNC Viewer by pasting a malformed payload into the VNC Server connection dialog, causing a denial of service.","user_interaction":"required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"VulnCheck","cpe":[],"cvss":{"score":4.6,"severity":"medium","source":"cna","vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N","version":"4.0"},"cwes":[{"id":"CWE-770","name":"Allocation of Resources Without Limits or Throttling"}],"description":"UltraVNC Viewer 1.2.4.0 contains a denial of service vulnerability that allows attackers to crash the application by manipulating VNC Server input. Attackers can generate a malformed 256-byte payload and paste it into the VNC Server connection dialog to trigger an application crash.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"weaponised"},"has_fix":null,"headline":"UltraVNC Viewer 1.2.4.0 - 'VNCServer' Denial of Service","id":"CVE-2020-37134","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"denial_of_service","year":"2020"},"n_packages":0,"n_references":3,"next":{"headline":"AMSS++ 4.7 - Backdoor Admin Account","id":"CVE-2020-37135"},"packages":[],"prev":{"headline":"UltraVNC Launcher 1.2.4.0 - 'RepeaterHost' Denial of Service","id":"CVE-2020-37133"},"products":["UltraVNC Viewer"],"published":"2026-02-05","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"yes","exploitation":"poc","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-03-05","vendors":["UltraVNC Team"]},"summary":"Attackers can crash UltraVNC Viewer by pasting a malformed payload into the VNC Server connection dialog, causing a denial of service.","url":"https://insights.sbomify.com/CVE-2020-37134/"}