{"answers":{"affected":"1 open source package ship an affected version, including janet.","exploited":"There is no known exploitation of OSV-2026-1309 in the wild and no public exploit code.","fix":"No fix has been published for OSV-2026-1309 yet. Limit exposure of the affected software until one is available.","what":"OSV-2026-1309 is a memory corruption vulnerability in janet, published on 21 Sep 2026."},"fix_prompt":"Check this codebase for OSV-2026-1309 and fix it if it is affected.\n\nWhat it is: OSV-2026-1309 is a memory corruption vulnerability in janet, published on 21 Sep 2026. \nExploitation: There is no known exploitation of OSV-2026-1309 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- janet (OSS-Fuzz): affected all versions; no fix listed\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/OSV-2026-1309/ (Markdown: https://insights.sbomify.com/OSV-2026-1309/index.md)","id":"OSV-2026-1309","markdown":"https://insights.sbomify.com/OSV-2026-1309/index.md","name":"OSV-2026-1309","record":{"aliases":[],"analysis":{"component_type":"library","fix_type":"patch","impacts":["denial_of_service","code_execution"],"network_reachable":"unknown","non_default_config":false,"product_category":"Janet programming language","requires_auth":"none","summary":"A heap-buffer-overflow in the Janet bytecode optimizer allows attackers to cause crashes or potentially execute arbitrary code via crafted bytecode.","user_interaction":"not_required","vuln_class":"memory_corruption"},"analysis_generated_by":"qwen3.8-flash-next","assigner":null,"cpe":[],"cvss":{"score":null,"severity":null,"source":null,"vector":null,"version":null},"cwes":[],"description":"OSS-Fuzz report: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=563659412\n\n```\nCrash type: Heap-buffer-overflow READ 4\nCrash state:\njanet_bytecode_movopt_basic_block\njanet_bytecode_movopt_full\njanet_bytecode_optimize\n```","ecosystems":["OSS-Fuzz"],"exploits":{"exploitdb":null,"first_seen":null,"github_poc":null,"max_poc_stars":null,"metasploit":null,"nuclei":null,"refs":[],"tier":null},"has_fix":false,"headline":"Heap-buffer-overflow in janet_bytecode_movopt_basic_block","id":"OSV-2026-1309","indexable":true,"kev":null,"kind":"advisory","links":{"ecosystem":"OSS-Fuzz","product":null,"products":[],"type":"memory_corruption","year":"2026"},"n_packages":1,"n_references":null,"packages":[{"ecosystem":"OSS-Fuzz","fixed":[],"introduced":[],"last_affected":[],"package":"janet","purl":"pkg:generic/janet","source":"OSV-2026-1309"}],"products":null,"published":"2026-09-21","related":[],"sources":[{"class":"attribution","licence":"CC BY 4.0","name":"OSS-Fuzz","prefix":"OSV"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":null,"updated":null,"vendors":null},"summary":"A heap-buffer-overflow in the Janet bytecode optimizer allows attackers to cause crashes or potentially execute arbitrary code via crafted bytecode.","url":"https://insights.sbomify.com/OSV-2026-1309/"}