{"answers":{"affected":"2 open source packages ship an affected version, including kobako.","exploited":"It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-55107 exists.","fix":"Upgrade kobako to 0.9.1 or later.","what":"CVE-2026-55107 is a critical code injection vulnerability in elct9620 kobako, published on 30 Sep 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-2026-55107 and fix it if it is affected.\n\nWhat it is: CVE-2026-55107 is a critical code injection vulnerability in elct9620 kobako, published on 30 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.\nExploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-55107 exists.\n\nAffected packages and fixed versions:\n- kobako (RubyGems): affected from 0.1.0; fixed in 0.9.1\n- kobako (RubyGems): affected from 0.1.0; fixed in 0.9.1\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-2026-55107/ (Markdown: https://insights.sbomify.com/CVE-2026-55107/index.md)","id":"CVE-2026-55107","markdown":"https://insights.sbomify.com/CVE-2026-55107/index.md","name":"CVE-2026-55107","record":{"aliases":["GHSA-7pwq-q9jf-539h"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["code_execution"],"network_reachable":"yes","non_default_config":false,"product_category":"Ruby sandbox library","requires_auth":"none","summary":"Attackers can escape the Kobako sandbox to execute arbitrary Ruby code on the host by exploiting method_missing and public_send flaws.","user_interaction":"not_required","vuln_class":"code_injection"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[],"cvss":{"score":10,"severity":"critical","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","version":"3.1"},"cwes":[{"id":"CWE-94","name":"Improper Control of Generation of Code"},{"id":"CWE-470","name":"Use of Externally-Controlled Input to Select Classes or Code"}],"description":"Kobako is a Ruby gem that embeds a Wasm-isolated mruby interpreter inside applications, allowing execution of untrusted Ruby scripts (LLM-generated code, user formulas, student submissions, third-party plugins) in-process without giving them access to host memory, files, network, or credentials. From version 0.1.0 to before version 0.9.1, a guest mruby script running inside the Kobako sandbox can execute arbitrary Ruby in the host process, fully escaping the sandbox. This issue has been patched in version 0.9.1.","ecosystems":["RubyGems"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"weaponised"},"has_fix":true,"headline":"Kobako Vulnerable to Sandbox Escape: guest eval reaches host RCE via method_missing → public_send (any bound Service)","id":"CVE-2026-55107","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"RubyGems","product":null,"products":[],"type":"code_injection","year":"2026"},"n_packages":2,"n_references":3,"next":{"headline":"KubeVela Terraform remote loader DoS via unbounded file read","id":"CVE-2026-55108"},"packages":[{"ecosystem":"RubyGems","fixed":["0.9.1"],"introduced":["0.1.0"],"last_affected":[],"package":"kobako","purl":null,"source":"GHSA-7pwq-q9jf-539h"},{"ecosystem":"RubyGems","fixed":["0.9.1"],"introduced":["0.1.0"],"last_affected":[],"package":"kobako","purl":"pkg:gem/kobako","source":"GHSA-7pwq-q9jf-539h"}],"prev":{"headline":"authentik: Unauthenticated LDAP directory data disclosure","id":"CVE-2026-55106"},"products":["kobako"],"published":"2026-09-30","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":"yes","exploitation":"poc","technical_impact":"total"},"state":"PUBLISHED","updated":"2026-09-30","vendors":["elct9620"]},"summary":"Attackers can escape the Kobako sandbox to execute arbitrary Ruby code on the host by exploiting method_missing and public_send flaws.","url":"https://insights.sbomify.com/CVE-2026-55107/"}