{"answers":{"affected":"4 open source packages ship an affected version, including Umbraco.Cms. It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-31834 in the wild and no public exploit code.","fix":"Upgrade Umbraco.Cms to a fixed version for your release line: 16.5.1 or 17.2.2.","what":"CVE-2026-31834 is a high-severity vulnerability in Umbraco Umbraco Cms, published on 10 Mar 2026. An attacker needs administrator access to exploit it, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-31834 and fix it if it is affected.\n\nWhat it is: CVE-2026-31834 is a high-severity vulnerability in Umbraco Umbraco Cms, published on 10 Mar 2026. An attacker needs administrator access to exploit it, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2026-31834 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- Umbraco.Cms (NuGet): affected from 15.3.1; fixed in 16.5.1\n- Umbraco.Cms (NuGet): affected from 15.3.1; fixed in 16.5.1\n- Umbraco.Cms (NuGet): affected from 17.0.0; fixed in 17.2.2\n- Umbraco.Cms (NuGet): affected from 17.0.0; fixed in 17.2.2\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-2026-31834/ (Markdown: https://insights.sbomify.com/CVE-2026-31834/index.md)","id":"CVE-2026-31834","markdown":"https://insights.sbomify.com/CVE-2026-31834/index.md","name":"CVE-2026-31834","record":{"aliases":["GHSA-rhcg-3h8r-v6vp"],"analysis":{"component_type":"web_application","fix_type":"upgrade","impacts":["privilege_escalation"],"network_reachable":"yes","non_default_config":false,"product_category":"Umbraco CMS","requires_auth":"high_privilege","summary":"Authenticated backoffice users can escalate privileges by assigning highly privileged roles due to missing authorization checks in Umbraco CMS.","user_interaction":"not_required","vuln_class":"privilege_escalation"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[{"product":"umbraco_cms","vendor":"umbraco"}],"cvss":{"score":7.2,"severity":"high","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H","version":"3.1"},"cwes":[{"id":"CWE-862","name":"Missing Authorization"},{"id":"CWE-284","name":"Improper Access Control"},{"id":"CWE-269","name":"Improper Privilege Management"}],"description":"Umbraco is an ASP.NET CMS. From 15.3.1 to before 16.5.1 and 17.2.2, A privilege escalation vulnerability has been identified in Umbraco CMS. Under certain conditions, authenticated backoffice users with permission to manage users, may be able to elevate their privileges due to insufficient authorization enforcement when modifying user group memberships. The affected functionality does not properly validate whether a user has sufficient privileges to assign highly privileged roles. This vulnerability is fixed in 16.5.1 and 17.2.2.","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":"Umbraco Affected by Vertical Privilege Escalation via Missing Authorization Checks","id":"CVE-2026-31834","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"NuGet","product":"umbraco:umbraco_cms","products":["umbraco:umbraco_cms"],"type":"privilege_escalation","year":"2026"},"n_packages":4,"n_references":1,"next":{"headline":"Vaultwarden WebAuthn credential metadata tampered before signature verification","id":"CVE-2026-31835"},"packages":[{"ecosystem":"NuGet","fixed":["16.5.1"],"introduced":["15.3.1"],"last_affected":[],"package":"Umbraco.Cms","purl":null,"source":"GHSA-rhcg-3h8r-v6vp"},{"ecosystem":"NuGet","fixed":["16.5.1"],"introduced":["15.3.1"],"last_affected":[],"package":"Umbraco.Cms","purl":"pkg:nuget/Umbraco.Cms","source":"GHSA-rhcg-3h8r-v6vp"},{"ecosystem":"NuGet","fixed":["17.2.2"],"introduced":["17.0.0"],"last_affected":[],"package":"Umbraco.Cms","purl":null,"source":"GHSA-rhcg-3h8r-v6vp"},{"ecosystem":"NuGet","fixed":["17.2.2"],"introduced":["17.0.0"],"last_affected":[],"package":"Umbraco.Cms","purl":"pkg:nuget/Umbraco.Cms","source":"GHSA-rhcg-3h8r-v6vp"}],"prev":{"headline":"Umbraco has Stored XSS in UFM Rendering Pipeline via Permissive DOMPurify Attribute Filtering","id":"CVE-2026-31833"},"products":["Umbraco-CMS"],"published":"2026-03-10","related":[{"cvss_score":10,"headline":"Umbraco CMS has an arbitrary file upload vulnerability","id":"CVE-2025-67288","kev_date_added":null,"published":"2025-12-22"},{"cvss_score":9.8,"headline":"File upload in n/a","id":"CVE-2014-10074","kev_date_added":null,"published":"2018-08-27"},{"cvss_score":9.8,"headline":"Server-side request forgery in n/a","id":"CVE-2012-1301","kev_date_added":null,"published":"2017-04-13"},{"cvss_score":9.3,"headline":"Umbraco CMS \u003c 4.7.1 codeEditorSave.asmx RCE","id":"CVE-2012-10054","kev_date_added":null,"published":"2025-08-13"},{"cvss_score":8.8,"headline":"Umbraco has a Management API Vulnerability to Path Traversal With Authenticated Users","id":"CVE-2025-32017","kev_date_added":null,"published":"2025-04-08"},{"cvss_score":8.8,"headline":"Umbraco CMS Authenticated File Upload","id":"CVE-2020-9471","kev_date_added":null,"published":"2020-03-16"},{"cvss_score":8.6,"headline":"Umbraco Remote ApplicationURL Overwrite","id":"CVE-2022-22690","kev_date_added":null,"published":"2022-01-18"}],"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":"US public information, NVD API terms","name":"NVD"},{"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":"2026-03-11","vendors":["umbraco"]},"summary":"Authenticated backoffice users can escalate privileges by assigning highly privileged roles due to missing authorization checks in Umbraco CMS.","url":"https://insights.sbomify.com/CVE-2026-31834/"}