{"answers":{"affected":"1 open source package ship an affected version, including ash_authentication_oauth2_server.","exploited":"There is no known exploitation of CVE-2026-82756 in the wild and no public exploit code.","fix":"Upgrade ash_authentication_oauth2_server to 0.3.1 or later.","what":"CVE-2026-82756 is a medium-severity vulnerability in ash-project ash_authentication_oauth2_server, published on 7 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-2026-82756 and fix it if it is affected.\n\nWhat it is: CVE-2026-82756 is a medium-severity vulnerability in ash-project ash_authentication_oauth2_server, published on 7 Sep 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-2026-82756 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- ash_authentication_oauth2_server (Hex): affected from 0.1.3; fixed in 0.3.1\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-2026-82756/ (Markdown: https://insights.sbomify.com/CVE-2026-82756/index.md)","id":"CVE-2026-82756","markdown":"https://insights.sbomify.com/CVE-2026-82756/index.md","name":"CVE-2026-82756","record":{"aliases":["EEF-CVE-2026-82756","GHSA-2h3v-83jg-2qmm"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["security_bypass"],"network_reachable":"yes","non_default_config":true,"product_category":"Elixir OAuth2 library","requires_auth":"none","summary":"An attacker can inject malicious authentication parameters into the WWW-Authenticate header in multi-tenant setups, potentially redirecting clients to attacker-controlled servers.","user_interaction":"not_required","vuln_class":"other"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"EEF","cpe":[],"cvss":{"score":6.3,"severity":"medium","source":"cna","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:L/SI:L/SA:N","version":"4.0"},"cwes":[{"id":"CWE-116","name":"Improper Encoding or Escaping of Output"}],"description":"Improper Encoding or Escaping of Output vulnerability in ash-project ash_authentication_oauth2_server allows an unauthenticated attacker to inject arbitrary authentication parameters into the WWW-Authenticate challenge header.\n\nBearerPlug and RequireScopePlug built the Bearer resource_metadata=\"...\" challenge by interpolating a resource_metadata URL derived from the request tenant directly into the quoted value. In a multi-tenant application that sets the Ash tenant from request-controlled data (a subdomain, the Host, a path segment, or a header), a tenant containing a \" closes the quoted value and appends attacker-chosen auth-params, including a second resource_metadata URL pointing at an attacker-controlled authorization server that spec-following clients follow. Carriage returns and line feeds are rejected by Plug, so this is parameter injection within one header, not response splitting.\n\nThis issue affects ash_authentication_oauth2_server: from 0.1.3 before 0.3.1.","ecosystems":["Hex"],"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":"Other in ash authentication oauth2 server","id":"CVE-2026-82756","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"Hex","product":null,"products":[],"type":"other","year":"2026"},"n_packages":1,"n_references":4,"next":{"headline":"ash_authentication_oauth2_server CIMD fetcher classifies IPv4-in-IPv6 and site-local addresses as public, allowing SSRF","id":"CVE-2026-82757"},"packages":[{"ecosystem":"Hex","fixed":["0.3.1"],"introduced":["0.1.3"],"last_affected":[],"package":"ash_authentication_oauth2_server","purl":"pkg:hex/ash_authentication_oauth2_server","source":"EEF-CVE-2026-82756"}],"prev":{"headline":"Information disclosure in ash authentication oauth2 server","id":"CVE-2026-82755"},"products":["ash_authentication_oauth2_server"],"published":"2026-09-07","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":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-09-08","vendors":["ash-project"]},"summary":"An attacker can inject malicious authentication parameters into the WWW-Authenticate header in multi-tenant setups, potentially redirecting clients to attacker-controlled servers.","url":"https://insights.sbomify.com/CVE-2026-82756/"}