{"answers":{"affected":"2 open source packages ship an affected version, including mdex and mdex_native.","exploited":"It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-53429 exists.","fix":"Upgrade mdex to 0.12.3 or later.","what":"CVE-2026-53429 is a medium-severity denial of service vulnerability in leandrocp mdex, published on 29 Jun 2026. It can only be exploited from the same machine or local network, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-53429 and fix it if it is affected.\n\nWhat it is: CVE-2026-53429 is a medium-severity denial of service vulnerability in leandrocp mdex, published on 29 Jun 2026. It can only be exploited from the same machine or local network, with no action from the victim.\nExploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-53429 exists.\n\nAffected packages and fixed versions:\n- mdex (Hex): affected from 0.11.0; fixed in 0.12.3\n- mdex_native (Hex): affected from 0.1.0; fixed in 0.2.3\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-2026-53429/ (Markdown: https://insights.sbomify.com/CVE-2026-53429/index.md)","id":"CVE-2026-53429","markdown":"https://insights.sbomify.com/CVE-2026-53429/index.md","name":"CVE-2026-53429","record":{"aliases":["EEF-CVE-2026-53429","GHSA-cmvp-gp9f-23xw"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Elixir Markdown library","requires_auth":"none","summary":"An attacker can cause unbounded memory exhaustion and crash the application by submitting documents with escaped tags to the mdex library.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"EEF","cpe":[],"cvss":{"score":6.9,"severity":"medium","source":"cna","vector":"CVSS:4.0/AV:L/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-401","name":"Missing Release of Memory after Effective Lifetime"}],"description":"Missing Release of Memory after Effective Lifetime vulnerability in leandrocp mdex and mdex_native allows an attacker who controls a rendered document to cause a denial of service through unbounded native memory exhaustion.\n\nThe native rendering code permanently leaks memory when rendering a document that contains escaped-tag nodes. The conversion of each %MDEx.EscapedTag{} node into its native representation (From\u003cExEscapedTag\u003e for NodeValue in the Rust NIF) calls Box::leak on the caller-supplied literal string, which surrenders the backing allocation so that it lives for the entire lifetime of the operating system process and is never freed.\n\nBoth the byte length of each literal and the number of escaped-tag nodes in a document are attacker-controlled, and there is no size cap, rate limit, or string interning on this path. Every render of a document containing escaped-tag nodes therefore leaks literal_size x node_count bytes that can never be reclaimed, and repeated renders accumulate without bound. Rendering reaches this path through the public MDEx.to_html/1 entry point and any other API that renders a supplied %MDEx.Document{}.\n\nAny application that uses mdex (or mdex_native directly) to render documents derived from user-supplied content is affected. Because the leaked memory is never reclaimed for the life of the BEAM process, an attacker can drive resident memory upward without limit until the node exhausts memory and crashes, taking down every process on it.\n\nThe vulnerable native code originally shipped inside mdex (in native/comrak_nif/src/types/document.rs) and was later extracted into the separate mdex_native package (native/mdex_native_nif/src/types/document.rs), where it remains unpatched.\n\nThis issue affects mdex from 0.11.0 before 0.12.3, and mdex_native from 0.1.0 before 0.2.3.","ecosystems":["Hex"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"weaponised"},"has_fix":true,"headline":"Unbounded native memory leak in mdex escaped-tag rendering enables unauthenticated denial of service","id":"CVE-2026-53429","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"Hex","product":null,"products":[],"type":"denial_of_service","year":"2026"},"n_packages":2,"n_references":4,"next":{"headline":"grpc gzip decompression bomb in GRPC.Compressor.Gzip.decompress/1","id":"CVE-2026-53430"},"packages":[{"ecosystem":"Hex","fixed":["0.12.3"],"introduced":["0.11.0"],"last_affected":[],"package":"mdex","purl":"pkg:hex/mdex","source":"EEF-CVE-2026-53429"},{"ecosystem":"Hex","fixed":["0.2.3"],"introduced":["0.1.0"],"last_affected":[],"package":"mdex_native","purl":"pkg:hex/mdex_native","source":"EEF-CVE-2026-53429"}],"prev":{"headline":"Unbounded memory allocation in highlight_lines range expansion in mdex","id":"CVE-2026-53428"},"products":["mdex","mdex_native"],"published":"2026-06-29","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"Erlang Ecosystem Foundation","prefix":"EEF"},{"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":"partial"},"state":"PUBLISHED","updated":"2026-06-30","vendors":["leandrocp"]},"summary":"An attacker can cause unbounded memory exhaustion and crash the application by submitting documents with escaped tags to the mdex library.","url":"https://insights.sbomify.com/CVE-2026-53429/"}