{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-117553 in the wild and no public exploit code.","fix":"No fix has been published for CVE-2026-117553 yet. Limit exposure of the affected software until one is available.","what":"CVE-2026-117553 is a high-severity vulnerability in Umbraco-CMS, published on 27 Oct 2026."},"fix_prompt":"Check this codebase for CVE-2026-117553 and fix it if it is affected.\n\nWhat it is: CVE-2026-117553 is a high-severity vulnerability in Umbraco-CMS, published on 27 Oct 2026. \nExploitation: There is no known exploitation of CVE-2026-117553 in the wild and no public exploit code.\n\nAffected product: Umbraco-CMS. No package-level version data is available, so check the vendor advisory linked from the reference page.\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-2026-117553/ (Markdown: https://insights.sbomify.com/CVE-2026-117553/index.md)","id":"CVE-2026-117553","markdown":"https://insights.sbomify.com/CVE-2026-117553/index.md","name":"CVE-2026-117553","record":{"aliases":["GHSA-r8f2-fxjr-gx5r","GHSA-rpv9-qp4c-g469"],"analysis":null,"analysis_generated_by":null,"assigner":"VulnCheck","cpe":[],"cvss":{"score":7.7,"severity":"high","source":"cna","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","version":"4.0"},"cwes":[{"id":"CWE-601","name":"URL Redirection to Untrusted Site"}],"description":"Umbraco CMS before 17.7.2 and 18.2.2 contains an authentication bypass vulnerability that allows unauthenticated attackers to register attacker-controlled OAuth redirect URIs by poisoning the Host header. Attackers send signed-in users authorization links using response_mode=form_post to capture codes, then redeem them via HTTP Basic client credentials to hijack back-office sessions and execute code through Razor templates.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":false,"headline":"Umbraco CMS before 17.7.2 and 18.2.2 Account Takeover via Host Header Poisoning","id":"CVE-2026-117553","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":null,"year":"2026"},"n_packages":0,"n_references":5,"next":{"headline":"Admidio before 5.0.17 Event Guest Restriction Bypass via events_function.php","id":"CVE-2026-117554"},"packages":[],"prev":{"headline":"A NULL pointer dereference flaw was found in 389-ds-base.","id":"CVE-2026-117548"},"products":["Umbraco-CMS"],"published":"2026-10-27","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2026-10-27","vendors":["umbraco"]},"summary":null,"url":"https://insights.sbomify.com/CVE-2026-117553/"}