{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2021-28904 in the wild and no public exploit code.","fix":"Upgrade to a fixed version.","what":"CVE-2021-28904 is a high-severity vulnerability in n/a, 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-2021-28904 and fix it if it is affected.\n\nWhat it is: CVE-2021-28904 is a high-severity vulnerability in n/a, 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-2021-28904 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-2021-28904/ (Markdown: https://insights.sbomify.com/CVE-2021-28904/index.md)","id":"CVE-2021-28904","markdown":"https://insights.sbomify.com/CVE-2021-28904/index.md","name":"CVE-2021-28904","record":{"aliases":["DEBIAN-CVE-2021-28904","GHSA-wqxj-4m27-ccp4","UBUNTU-CVE-2021-28904"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"libyang library","requires_auth":"none","summary":"A null pointer dereference in libyang allows attackers to cause a denial of service via a crafted input with a NULL revision value.","user_interaction":"not_required","vuln_class":"null_dereference"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"mitre","cpe":[{"product":"libyang","vendor":"cesnet"}],"cvss":{"score":7.5,"severity":"high","source":"nvd","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},"cwes":[{"id":"CWE-252","name":"Unchecked Return Value"}],"description":"In function ext_get_plugin() in libyang \u003c= v1.0.225, it doesn't check whether the value of revision is NULL. If revision is NULL, the operation of strcmp(revision, ext_plugins[u].revision) will lead to a crash.","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":"Null dereference in n/a","id":"CVE-2021-28904","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"null_dereference","year":"2021"},"n_packages":0,"n_references":2,"next":{"headline":"Denial of service in n/a","id":"CVE-2021-28905"},"packages":[],"prev":{"headline":"Denial of service in n/a","id":"CVE-2021-28903"},"products":["n/a"],"published":"2021-05-20","related":[{"cvss_score":8.8,"headline":"Memory corruption in n/a","id":"CVE-2019-20393","kev_date_added":null,"published":"2020-01-22"},{"cvss_score":8.8,"headline":"Use after free in n/a","id":"CVE-2019-20394","kev_date_added":null,"published":"2020-01-22"},{"cvss_score":8.8,"headline":"Memory corruption in n/a","id":"CVE-2019-20397","kev_date_added":null,"published":"2020-01-22"},{"cvss_score":8.1,"headline":"Memory corruption in libyang","id":"CVE-2019-19333","kev_date_added":null,"published":"2019-12-06"},{"cvss_score":8.1,"headline":"Memory corruption in libyang","id":"CVE-2019-19334","kev_date_added":null,"published":"2019-12-06"},{"cvss_score":7.5,"headline":"Null dereference in n/a","id":"CVE-2023-26917","kev_date_added":null,"published":"2023-04-11"},{"cvss_score":7.5,"headline":"Null dereference in n/a","id":"CVE-2021-28902","kev_date_added":null,"published":"2021-05-20"}],"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":"A null pointer dereference in libyang allows attackers to cause a denial of service via a crafted input with a NULL revision value.","url":"https://insights.sbomify.com/CVE-2021-28904/"}