{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-66046 in the wild and no public exploit code.","fix":"Upgrade to a fixed version.","what":"CVE-2026-66046 is a high-severity denial of service vulnerability in Libexpat Project Libexpat, published on 18 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-66046 and fix it if it is affected.\n\nWhat it is: CVE-2026-66046 is a high-severity denial of service vulnerability in Libexpat Project Libexpat, published on 18 Aug 2026. 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-2026-66046 in the wild and no public exploit code.\n\nAffected product: Libexpat Project Libexpat. 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-2026-66046/ (Markdown: https://insights.sbomify.com/CVE-2026-66046/index.md)","id":"CVE-2026-66046","markdown":"https://insights.sbomify.com/CVE-2026-66046/index.md","name":"CVE-2026-66046","record":{"aliases":["ALPINE-CVE-2026-66046","AZL-96605","BELL-CVE-2026-66046","CLSA-2026-1790064092","CLSA-2026-1790153508","CLSA-2026-1790239193","CLSA-2026-1790239270","CLSA-2026-1790239757","DEBIAN-CVE-2026-66046","ECHO-38c1-1304-759b","GHSA-m3rp-25vq-jfcv","ROOT-OS-DEBIAN-11-CVE-2026-66046","UBUNTU-CVE-2026-66046"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"XML parsing library","requires_auth":"none","summary":"Remote attackers can cause denial of service in applications using Expat by submitting large XML documents that trigger quadratic complexity in attribute processing.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"VulnCheck","cpe":[{"product":"libexpat","vendor":"libexpat_project"}],"cvss":{"score":8.7,"severity":"high","source":"cna","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","version":"4.0"},"cwes":[{"id":"CWE-407","name":"Inefficient Algorithmic Complexity"}],"description":"Expat through 2.8.3 contains a denial of service vulnerability caused by quadratic algorithmic complexity in the storeAtts() function in xmlparse.c, where processing N specified attributes with non-normalized values triggers an O(N^2) linear scan of elementType-\u003edefaultAtts to determine CDATA status. A remote unauthenticated attacker can supply a single well-formed XML document of a few megabytes to an application parsing untrusted XML to cause excessive CPU consumption, resulting in denial of service without requiring authentication, external entity resolution, or non-default parser options.","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":"Expat Denial of Service via storeAtts() Quadratic Complexity","id":"CVE-2026-66046","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"libexpat_project:libexpat","products":["libexpat_project:libexpat"],"type":"denial_of_service","year":"2026"},"n_packages":0,"n_references":2,"next":{"headline":"ProfilePress WordPress Plugin \u003c 4.17.2 Unauthenticated Arbitrary Plugin Installation RCE","id":"CVE-2026-66047"},"packages":[],"prev":{"headline":"This CVE ID has been rejected or withdrawn by its CVE Numbering Authority.","id":"CVE-2026-66045"},"products":["libexpat"],"published":"2026-08-18","related":[{"cvss_score":9.8,"headline":"Integer overflow in n/a","id":"CVE-2024-45490","kev_date_added":null,"published":"2024-08-30"},{"cvss_score":8.1,"headline":"Integer overflow in n/a","id":"CVE-2021-46143","kev_date_added":null,"published":"2022-01-06"},{"cvss_score":7.8,"headline":"Privilege escalation in n/a","id":"CVE-2017-11742","kev_date_added":null,"published":"2017-07-30"},{"cvss_score":7.5,"headline":"Denial of service in libexpat","id":"CVE-2025-59375","kev_date_added":null,"published":"2025-09-15"},{"cvss_score":7.5,"headline":"Denial of service in n/a","id":"CVE-2023-52425","kev_date_added":null,"published":"2024-02-04"},{"cvss_score":7.3,"headline":"Integer overflow in n/a","id":"CVE-2024-45491","kev_date_added":null,"published":"2024-08-30"}],"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":"yes","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-10-01","vendors":["libexpat project"]},"summary":"Remote attackers can cause denial of service in applications using Expat by submitting large XML documents that trigger quadratic complexity in attribute processing.","url":"https://insights.sbomify.com/CVE-2026-66046/"}