{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2021-27434 in the wild and no public exploit code.","fix":"No fix has been published for CVE-2021-27434 yet. Limit exposure of the affected software until one is available.","what":"CVE-2021-27434 is a high-severity denial of service vulnerability in OPC UA Products Built with the .NET Framework 4.5, 4.0, and 3.5, published on 20 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-2021-27434 and fix it if it is affected.\n\nWhat it is: CVE-2021-27434 is a high-severity denial of service vulnerability in OPC UA Products Built with the .NET Framework 4.5, 4.0, and 3.5, published on 20 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-2021-27434 in the wild and no public exploit code.\n\nAffected product: OPC UA Products Built with the .NET Framework 4.5, 4.0, and 3.5. 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-2021-27434/ (Markdown: https://insights.sbomify.com/CVE-2021-27434/index.md)","id":"CVE-2021-27434","markdown":"https://insights.sbomify.com/CVE-2021-27434/index.md","name":"CVE-2021-27434","record":{"aliases":["GHSA-43g9-fmq9-jjpm"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"OPC UA SDK","requires_auth":"none","summary":"An attacker can trigger a stack overflow via uncontrolled recursion in the Unified Automation .NET OPC UA SDK, causing a denial of service.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"icscert","cpe":[{"product":".net_based_opc_ua_client\\/server_sdk","vendor":"unified-automation"}],"cvss":{"score":7.5,"severity":"high","source":"nvd","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","version":"3.1"},"cwes":[{"id":"CWE-674","name":"Uncontrolled Recursion"},{"id":"CWE-200","name":"Exposure of Sensitive Information to an Unauthorized Actor"}],"description":"Products with Unified Automation .NET based OPC UA Client/Server SDK Bundle: Versions V3.0.7 and prior (.NET 4.5, 4.0, and 3.5 Framework versions only) are vulnerable to an uncontrolled recursion, which may allow an attacker to trigger a stack overflow.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":null,"headline":"Denial of service in OPC UA Products Built with the .NET Framework 4.5, 4.0, and 3.5","id":"CVE-2021-27434","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"denial_of_service","year":"2021"},"n_packages":0,"n_references":1,"next":{"headline":"ARM mbed Integer Overflow or Wraparound","id":"CVE-2021-27435"},"packages":[],"prev":{"headline":"ARM mbed-ualloc memory library Integer Overflow or Wraparound","id":"CVE-2021-27433"},"products":["OPC UA Products Built with the .NET Framework 4.5, 4.0, and 3.5"],"published":"2021-05-20","related":[],"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":"An attacker can trigger a stack overflow via uncontrolled recursion in the Unified Automation .NET OPC UA SDK, causing a denial of service.","url":"https://insights.sbomify.com/CVE-2021-27434/"}