{"answers":{"affected":"It affects 1 product.","exploited":"It is not confirmed as exploited in the wild, but public exploit code for CVE-2021-21958 exists.","fix":"No fix has been published for CVE-2021-21958 yet. Limit exposure of the affected software until one is available.","what":"CVE-2021-21958 is a high-severity memory corruption vulnerability in Hancom, published on 16 Feb 2022. 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-2021-21958 and fix it if it is affected.\n\nWhat it is: CVE-2021-21958 is a high-severity memory corruption vulnerability in Hancom, published on 16 Feb 2022. 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-2021-21958 exists.\n\nAffected product: Hancom. 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-2021-21958/ (Markdown: https://insights.sbomify.com/CVE-2021-21958/index.md)","id":"CVE-2021-21958","markdown":"https://insights.sbomify.com/CVE-2021-21958/index.md","name":"CVE-2021-21958","record":{"aliases":["GHSA-5fcw-h565-mjpq"],"analysis":{"component_type":"desktop_application","fix_type":"patch","impacts":["code_execution"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Hancom Office","requires_auth":"none","summary":"A heap-based buffer overflow in Hancom Office allows attackers to execute arbitrary code via a specially crafted file.","user_interaction":"required","vuln_class":"memory_corruption"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"talos","cpe":[{"product":"hancom_office_2020","vendor":"hancom"}],"cvss":{"score":7.8,"severity":"high","source":"cna","vector":"CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","version":"3.0"},"cwes":[{"id":"CWE-787","name":"Out-of-bounds Write"},{"id":"CWE-122","name":"Heap-based Buffer Overflow"}],"description":"A heap-based buffer overflow vulnerability exists in the Hword HwordApp.dll functionality of Hancom Office 2020 11.0.0.2353. A specially-crafted malformed file can lead to memory corruption and potential arbitrary code execution. An attacker can provide a malicious file to trigger this vulnerability.","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":"Memory corruption in Hancom","id":"CVE-2021-21958","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"memory_corruption","year":"2021"},"n_packages":0,"n_references":1,"next":{"headline":"Misconfiguration in Sealevel","id":"CVE-2021-21959"},"packages":[],"prev":{"headline":"Command injection in Dream Report","id":"CVE-2021-21957"},"products":["Hancom"],"published":"2022-02-16","related":[{"cvss_score":8.8,"headline":"Use after free in Hancom Office 2020","id":"CVE-2023-32541","kev_date_added":null,"published":"2023-09-26"},{"cvss_score":7.8,"headline":"Memory corruption in Hancom Office 2020","id":"CVE-2022-33896","kev_date_added":null,"published":"2022-10-07"}],"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":"no","exploitation":"poc","technical_impact":"total"},"state":"PUBLISHED","updated":"2025-04-15","vendors":["n/a"]},"summary":"A heap-based buffer overflow in Hancom Office allows attackers to execute arbitrary code via a specially crafted file.","url":"https://insights.sbomify.com/CVE-2021-21958/"}