{"answers":{"affected":"4 open source packages ship an affected version, including jwt.","exploited":"There is no known exploitation of CVE-2026-45363 in the wild and no public exploit code.","fix":"Upgrade jwt to a fixed version for your release line: 2.10.3 or 3.2.0.","what":"CVE-2026-45363 is a critical authentication bypass vulnerability in ruby-jwt, published on 14 Jul 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-2026-45363 and fix it if it is affected.\n\nWhat it is: CVE-2026-45363 is a critical authentication bypass vulnerability in ruby-jwt, published on 14 Jul 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-2026-45363 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- jwt (RubyGems): affected all versions; fixed in 2.10.3\n- jwt (RubyGems): affected all versions; fixed in 2.10.3\n- jwt (RubyGems): affected from 3.0.0; fixed in 3.2.0\n- jwt (RubyGems): affected from 3.0.0; fixed in 3.2.0\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-2026-45363/ (Markdown: https://insights.sbomify.com/CVE-2026-45363/index.md)","id":"CVE-2026-45363","markdown":"https://insights.sbomify.com/CVE-2026-45363/index.md","name":"CVE-2026-45363","record":{"aliases":["DEBIAN-CVE-2026-45363","GHSA-c32j-vqhx-rx3x","MINI-4rmj-7r6x-82rp","MINI-9mmf-hm45-p85q","MINI-9w58-pgcp-fc4j","UBUNTU-CVE-2026-45363"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["security_bypass"],"network_reachable":"yes","non_default_config":false,"product_category":"Ruby JWT library","requires_auth":"none","summary":"Attackers can forge valid JWT tokens by exploiting empty-key HMAC verification flaws in the ruby-jwt library, bypassing authentication checks.","user_interaction":"not_required","vuln_class":"auth_bypass"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[],"cvss":{"score":9.1,"severity":"critical","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","version":"3.1"},"cwes":[{"id":"CWE-326","name":"Inadequate Encryption Strength"},{"id":"CWE-287","name":"Improper Authentication"},{"id":"CWE-1391","name":"Use of Weak Credentials"}],"description":"ruby-jwt is a Ruby implementation of the RFC 7519 OAuth JSON Web Token standard. Prior to 2.10.3 and 3.2.0, JWT.decode(token, '', true, algorithm: 'HS256') accepts an attacker-forged token because OpenSSL::HMAC.digest('SHA256', '', payload) returns a valid digest under an empty key and no empty-key precondition exists in the HMAC algorithm. The same path is reached when a keyfinder block or key_finder: argument returns an empty string, nil, or an array containing nil for an unknown key, affecting HS256, HS384, and HS512 verification through JWT.decode and JWT::EncodedToken#verify_signature!. This issue is fixed in versions 2.10.3 and 3.2.0.","ecosystems":["RubyGems"],"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":"`jwt` (Ruby gem) - empty-key HMAC bypass","id":"CVE-2026-45363","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"RubyGems","product":null,"products":[],"type":"auth_bypass","year":"2026"},"n_packages":4,"n_references":5,"next":{"headline":"Better Auth: Rate limiter keys IPv6 addresses individually and is bypassable via prefix rotation","id":"CVE-2026-45364"},"packages":[{"ecosystem":"RubyGems","fixed":["2.10.3"],"introduced":["0"],"last_affected":[],"package":"jwt","purl":null,"source":"GHSA-c32j-vqhx-rx3x"},{"ecosystem":"RubyGems","fixed":["2.10.3"],"introduced":["0"],"last_affected":[],"package":"jwt","purl":"pkg:gem/jwt","source":"GHSA-c32j-vqhx-rx3x"},{"ecosystem":"RubyGems","fixed":["3.2.0"],"introduced":["3.0.0"],"last_affected":[],"package":"jwt","purl":null,"source":"GHSA-c32j-vqhx-rx3x"},{"ecosystem":"RubyGems","fixed":["3.2.0"],"introduced":["3.0.0"],"last_affected":[],"package":"jwt","purl":"pkg:gem/jwt","source":"GHSA-c32j-vqhx-rx3x"}],"prev":{"headline":"Information disclosure in Switchvox","id":"CVE-2026-45362"},"products":["ruby-jwt"],"published":"2026-07-14","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":"none","technical_impact":"total"},"state":"PUBLISHED","updated":"2026-09-19","vendors":["jwt"]},"summary":"Attackers can forge valid JWT tokens by exploiting empty-key HMAC verification flaws in the ruby-jwt library, bypassing authentication checks.","url":"https://insights.sbomify.com/CVE-2026-45363/"}