{"answers":{"affected":"4 open source packages ship an affected version, including CoreWCF.Primitives.","exploited":"There is no known exploitation of CVE-2026-54781 in the wild and no public exploit code.","fix":"Upgrade CoreWCF.Primitives to a fixed version for your release line: 1.8.1 or 1.9.1.","what":"CVE-2026-54781 is a high-severity authentication bypass vulnerability in CoreWCF, published on 8 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-2026-54781 and fix it if it is affected.\n\nWhat it is: CVE-2026-54781 is a high-severity authentication bypass vulnerability in CoreWCF, published on 8 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-2026-54781 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- CoreWCF.Primitives (NuGet): affected all versions; fixed in 1.8.1\n- CoreWCF.Primitives (NuGet): affected all versions; fixed in 1.8.1\n- CoreWCF.Primitives (NuGet): affected from 1.9.0; fixed in 1.9.1\n- CoreWCF.Primitives (NuGet): affected from 1.9.0; fixed in 1.9.1\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-2026-54781/ (Markdown: https://insights.sbomify.com/CVE-2026-54781/index.md)","id":"CVE-2026-54781","markdown":"https://insights.sbomify.com/CVE-2026-54781/index.md","name":"CVE-2026-54781","record":{"aliases":["GHSA-48pq-2xq3-c2m4"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["security_bypass"],"network_reachable":"yes","non_default_config":false,"product_category":"CoreWCF library","requires_auth":"none","summary":"Attackers can bypass SAML authentication in CoreWCF by exploiting missing SubjectConfirmation and holder-of-key validation, allowing unauthorized access.","user_interaction":"not_required","vuln_class":"auth_bypass"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[],"cvss":{"score":7.4,"severity":"high","source":"cna","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","version":"3.1"},"cwes":[{"id":"CWE-345","name":"Insufficient Verification of Data Authenticity"},{"id":"CWE-287","name":"Improper Authentication"}],"description":"CoreWCF is a port of the service side of Windows Communication Foundation (WCF) to .NET Core. Prior to 1.8.1 and 1.9.1, CoreWCF SAML token validation does not enforce SubjectConfirmation method URIs or holder-of-key proof keys in SamlSecurityTokenHandler, allowing holder-of-key downgrade or custom confirmation method assertions to authenticate a subject without proving authority over the assertion. This issue is fixed in versions 1.8.1 and 1.9.1.","ecosystems":["NuGet"],"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":"CoreWCF: SAML SubjectConfirmation methods and holder-of-key proof keys are not enforced","id":"CVE-2026-54781","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"NuGet","product":null,"products":[],"type":"auth_bypass","year":"2026"},"n_packages":4,"n_references":6,"next":{"headline":"CoreWCF: Authentication bypass in CoreWCF SAML 1.1 / 2.0 token signature validation","id":"CVE-2026-54782"},"packages":[{"ecosystem":"NuGet","fixed":["1.8.1"],"introduced":["0"],"last_affected":[],"package":"CoreWCF.Primitives","purl":null,"source":"GHSA-48pq-2xq3-c2m4"},{"ecosystem":"NuGet","fixed":["1.8.1"],"introduced":["0"],"last_affected":[],"package":"CoreWCF.Primitives","purl":"pkg:nuget/CoreWCF.Primitives","source":"GHSA-48pq-2xq3-c2m4"},{"ecosystem":"NuGet","fixed":["1.9.1"],"introduced":["1.9.0"],"last_affected":[],"package":"CoreWCF.Primitives","purl":null,"source":"GHSA-48pq-2xq3-c2m4"},{"ecosystem":"NuGet","fixed":["1.9.1"],"introduced":["1.9.0"],"last_affected":[],"package":"CoreWCF.Primitives","purl":"pkg:nuget/CoreWCF.Primitives","source":"GHSA-48pq-2xq3-c2m4"}],"prev":{"headline":"CoreWCF: WS-Security Reference DigestMethod Algorithm-Suite Bypass","id":"CVE-2026-54780"},"products":["CoreWCF"],"published":"2026-07-08","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":"no","exploitation":"none","technical_impact":"total"},"state":"PUBLISHED","updated":"2026-07-09","vendors":["CoreWCF"]},"summary":"Attackers can bypass SAML authentication in CoreWCF by exploiting missing SubjectConfirmation and holder-of-key validation, allowing unauthorized access.","url":"https://insights.sbomify.com/CVE-2026-54781/"}