{"answers":{"affected":"1 open source package ship an affected version, including hono.","exploited":"There is no known exploitation of CVE-2026-126356 in the wild and no public exploit code.","exposure":"An affected version is only exploitable if your software calls validator('form'). Many projects that include it are not exposed.","fix":"Upgrade hono to 4.13.16 or later.","what":"CVE-2026-126356 is a medium-severity security feature bypass vulnerability in honojs hono, published on 12 Nov 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-2026-126356 and fix it if it is affected.\n\nWhat it is: CVE-2026-126356 is a medium-severity security feature bypass vulnerability in honojs hono, published on 12 Nov 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-2026-126356 in the wild and no public exploit code.\nExposure: An affected version is only exploitable if your software calls validator('form'). Many projects that include it are not exposed.\n\nAffected packages and fixed versions:\n- hono (npm): affected from 4.5.1; fixed in 4.13.16\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.\n   If an affected version is present, also search the code for calls to validator('form') and report whether any exist.\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-2026-126356/ (Markdown: https://insights.sbomify.com/CVE-2026-126356/index.md)","id":"CVE-2026-126356","markdown":"https://insights.sbomify.com/CVE-2026-126356/index.md","name":"CVE-2026-126356","record":{"aliases":["GHSA-4h7h-rv7c-7m2v"],"analysis":{"component_type":"library","exploitable_when_present":false,"fix_type":"upgrade","impacts":["security_bypass"],"network_reachable":"yes","non_default_config":true,"product_category":"JavaScript web framework","requires_auth":"none","requires_specific_call":true,"summary":"Unauthenticated clients can bypass Hono form validator allow-lists or required checks using multipart requests with extra parameters.","user_interaction":"not_required","vuln_class":"security_feature_bypass","vulnerable_functions":["validator('form')"]},"analysis_generated_by":"sbomify/insights-2b-fp8","assigner":"GitHub_M","cpe":[],"cvss":{"score":5.3,"severity":"medium","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","version":"3.1"},"cwes":[{"id":"CWE-20","name":"Improper Input Validation"},{"id":"CWE-1471","name":"Insufficiently Controlled Parser Differential"}],"description":"Hono is a Web application framework that provides support for any JavaScript runtime. From 4.5.1 until 4.13.16, validator('form') uses a strict whole-header pattern that fails to recognize multipart/form-data when its Content-Type includes another legal parameter or extra whitespace after a semicolon. The validation callback receives an empty object even though c.req.parseBody() or c.req.formData() can still parse and expose all submitted fields to the handler. An unauthenticated client can therefore bypass allow-list or required-field checks when the application relies on the form validator and its callback accepts an empty object. application/x-www-form-urlencoded requests are not affected. This issue is fixed in version 4.13.16.","ecosystems":["npm"],"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":"Hono: `validator('form')` skips validation for `multipart/form-data` requests with extra parameters","id":"CVE-2026-126356","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"npm","product":null,"products":[],"type":"security_feature_bypass","year":"2026"},"n_packages":1,"n_references":3,"next":{"headline":"Hono: `mount()` and `app.mount()` can forward a path that bypasses middleware scoped inside the mount prefix","id":"CVE-2026-126357"},"nickname":null,"packages":[{"ecosystem":"npm","fixed":["4.13.16"],"introduced":["4.5.1"],"last_affected":[],"package":"hono","purl":null,"source":"GHSA-4h7h-rv7c-7m2v"}],"prev":{"headline":"Hono: `csrf()` does not check requests sent by hyperlink auditing (`text/ping`)","id":"CVE-2026-126355"},"products":["hono"],"published":"2026-11-12","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"GitHub Advisory Database","prefix":"GHSA"},{"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":"2026-11-12","vendors":["honojs"]},"summary":"Unauthenticated clients can bypass Hono form validator allow-lists or required checks using multipart requests with extra parameters.","url":"https://insights.sbomify.com/CVE-2026-126356/"}