{"answers":{"affected":"It affects 1 product.","exploited":"It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-6686 exists.","fix":"No fix has been published for CVE-2026-6686 yet. Limit exposure of the affected software until one is available.","what":"CVE-2026-6686 is a medium-severity vulnerability in ChaN FatFs, published on 1 Jul 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-2026-6686 and fix it if it is affected.\n\nWhat it is: CVE-2026-6686 is a medium-severity vulnerability in ChaN FatFs, published on 1 Jul 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-2026-6686 exists.\n\nAffected product: ChaN FatFs. 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-2026-6686/ (Markdown: https://insights.sbomify.com/CVE-2026-6686/index.md)","id":"CVE-2026-6686","markdown":"https://insights.sbomify.com/CVE-2026-6686/index.md","name":"CVE-2026-6686","record":{"aliases":["GHSA-h94p-vjqx-v7rr"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["data_read"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"FatFs file system library","requires_auth":"none","summary":"Attackers with physical access can read uninitialized memory from newly allocated clusters when extending files past EOF in FatFs.","user_interaction":"not_required","vuln_class":"information_disclosure"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"runZero","cpe":[{"product":"fatfs","vendor":"elm-chan"}],"cvss":{"score":4.6,"severity":"medium","source":"cna","vector":"CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","version":"3.1"},"cwes":[{"id":"CWE-908","name":"Use of Uninitialized Resource"}],"description":"FatFs R0.16 and earlier contains an uninitialized cluster exposure when f_lseek() extends files beyond EOF without zero-filling newly allocated clusters. This maps to CWE-908 (Use of Uninitialized Resource). Estimated CVSS v3.1 vector: CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N (4.6, Medium). The estimated CISA SSVC vectors are Exploitation: PoC, Technical Impact: Partial.","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":"FatFs Use of Uninitialized Clusters After Seek Past EOF","id":"CVE-2026-6686","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"information_disclosure","year":"2026"},"n_packages":0,"n_references":4,"next":{"headline":"FatFs Stack Buffer Overflow via Uncapped exFAT Label Length","id":"CVE-2026-6687"},"packages":[],"prev":{"headline":"This CVE ID has been rejected or withdrawn by its CVE Numbering Authority following a notification that the vulnerability determination was made in error.","id":"CVE-2026-6685"},"products":["FatFs"],"published":"2026-07-01","related":[{"cvss_score":7.6,"headline":"FatFs Integer Overflow in FAT32 Volume Mount","id":"CVE-2026-6682","kev_date_added":null,"published":"2026-07-01"},{"cvss_score":7.6,"headline":"FatFs Stack Buffer Overflow via Uncapped exFAT Label Length","id":"CVE-2026-6687","kev_date_added":null,"published":"2026-07-01"},{"cvss_score":7.6,"headline":"FatFs Buffer Overflow via Unbounded LFN Filename Copy","id":"CVE-2026-6688","kev_date_added":null,"published":"2026-07-01"},{"cvss_score":4.6,"headline":"FatFs Divide-by-Zero in exFAT Sync","id":"CVE-2026-6683","kev_date_added":null,"published":"2026-07-01"},{"cvss_score":4.6,"headline":"FatFs Infinite Loop in GPT Partition Scan","id":"CVE-2026-6684","kev_date_added":null,"published":"2026-07-01"}],"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":"partial"},"state":"PUBLISHED","updated":"2026-07-01","vendors":["ChaN"]},"summary":"Attackers with physical access can read uninitialized memory from newly allocated clusters when extending files past EOF in FatFs.","url":"https://insights.sbomify.com/CVE-2026-6686/"}