{"answers":{"affected":"1 open source package ship an affected version, including oidcc.","exploited":"It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-75759 exists.","fix":"Upgrade oidcc to 3.9.0 or later.","what":"CVE-2026-75759 is a high-severity authentication bypass vulnerability in erlef oidcc, published on 30 Aug 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link."},"fix_prompt":"Check this codebase for CVE-2026-75759 and fix it if it is affected.\n\nWhat it is: CVE-2026-75759 is a high-severity authentication bypass vulnerability in erlef oidcc, published on 30 Aug 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.\nExploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-75759 exists.\n\nAffected packages and fixed versions:\n- oidcc (Hex): affected from 3.2.0-beta.1; fixed in 3.9.0\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-2026-75759/ (Markdown: https://insights.sbomify.com/CVE-2026-75759/index.md)","id":"CVE-2026-75759","markdown":"https://insights.sbomify.com/CVE-2026-75759/index.md","name":"CVE-2026-75759","record":{"aliases":["EEF-CVE-2026-75759","GHSA-533g-4vf3-xwrj"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["account_takeover","security_bypass"],"network_reachable":"yes","non_default_config":false,"product_category":"Erlang OIDC library","requires_auth":"none","summary":"An attacker can impersonate any user by sending an encrypted but unsigned ID token or JARM response, bypassing signature verification in the oidcc library.","user_interaction":"required","vuln_class":"auth_bypass"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"EEF","cpe":[],"cvss":{"score":7.6,"severity":"high","source":"cna","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N","version":"4.0"},"cwes":[{"id":"CWE-347","name":"Improper Verification of Cryptographic Signature"}],"description":"Improper Verification of Cryptographic Signature vulnerability in erlef oidcc allows an unauthenticated attacker to impersonate an arbitrary user via an encrypted ID token or JARM response carrying no nested signature. OpenID Connect Core 1.0 section 2 requires that an encrypted ID token be signed then encrypted, with the result being a Nested JWT, and JARM processing rule 5 requires the client to check the signature unconditionally. oidcc instead accepted a JWE wrapping unsigned claims as fully validated, so anyone holding the relying party's public encryption key could mint a token with an arbitrary sub, iss, and aud without possessing the provider's signing key.\n\nIn oidcc_jwt_util:verify_decrypted_token/4, a decrypted payload that is not a signed JWS fell back to parsing the plaintext claims and returning them with no verifying key. oidcc_token:int_validate_jwt/4 then matched on the JOSE structure type rather than on whether a signature had been verified, and returned success. The JARM path in oidcc_token:validate_jarm/3 is reachable through the browser front channel. UserInfo responses are not affected, because OpenID Connect Core 1.0 section 5.3.2 permits them to be encrypted without also being signed.\n\nThis issue affects oidcc: from 3.2.0-beta.1 before 3.9.0.","ecosystems":["Hex"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"weaponised"},"has_fix":true,"headline":"Encrypted ID token or JARM response accepted without a nested signature in erlef oidcc","id":"CVE-2026-75759","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"Hex","product":null,"products":[],"type":"auth_bypass","year":"2026"},"n_packages":1,"n_references":4,"next":{"headline":"AshAi vectorize change leaks raw embedding-provider errors, including credentials, in a user-facing error","id":"CVE-2026-75760"},"packages":[{"ecosystem":"Hex","fixed":["3.9.0"],"introduced":["3.2.0-beta.1"],"last_affected":[],"package":"oidcc","purl":"pkg:hex/oidcc","source":"EEF-CVE-2026-75759"}],"prev":{"headline":"Unbounded recursion between Inspect.List charlist rendering and List.to_string/1 error path in Elixir","id":"CVE-2026-75758"},"products":["oidcc"],"published":"2026-08-30","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"Erlang Ecosystem Foundation","prefix":"EEF"},{"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":"total"},"state":"PUBLISHED","updated":"2026-08-31","vendors":["erlef"]},"summary":"An attacker can impersonate any user by sending an encrypted but unsigned ID token or JARM response, bypassing signature verification in the oidcc library.","url":"https://insights.sbomify.com/CVE-2026-75759/"}