{"answers":{"affected":"3 open source packages ship an affected version, including open-webui. It affects 1 product.","exploited":"It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-87011 exists.","fix":"Upgrade open-webui to 0.11.1 or later.","what":"CVE-2026-87011 is a high-severity denial of service vulnerability in Openwebui Open Webui, published on 9 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-2026-87011 and fix it if it is affected.\n\nWhat it is: CVE-2026-87011 is a high-severity denial of service vulnerability in Openwebui Open Webui, published on 9 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.\nExploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-87011 exists.\n\nAffected packages and fixed versions:\n- open-webui (PyPI): affected from 0.9.0; fixed in 0.11.1\n- open-webui (PyPI): affected from 0.9.0; fixed in 0.11.1\n- open-webui (PyPI): affected from 0.9.0; fixed in 0.11.1\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-2026-87011/ (Markdown: https://insights.sbomify.com/CVE-2026-87011/index.md)","id":"CVE-2026-87011","markdown":"https://insights.sbomify.com/CVE-2026-87011/index.md","name":"CVE-2026-87011","record":{"aliases":["GHSA-3g9q-v48f-hh9w","PYSEC-2026-4117"],"analysis":{"component_type":"web_application","fix_type":"upgrade","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":true,"product_category":"Open WebUI AI platform","requires_auth":"none","summary":"Unauthenticated attackers can cause denial of service in Open WebUI by sending invalid logout tokens that trigger uncached network fetches and block the event loop.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[{"product":"open_webui","vendor":"openwebui"}],"cvss":{"score":7.5,"severity":"high","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},"cwes":[{"id":"CWE-770","name":"Allocation of Resources Without Limits or Throttling"},{"id":"CWE-405","name":"Asymmetric Resource Consumption (Amplification)"}],"description":"Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.9.0 until 0.11.1, the unauthenticated POST /oauth/backchannel-logout handler in backend/open_webui/utils/oauth.py fetched the OIDC discovery document and signing keys before validating a submitted logout token. Each request repeated uncached network fetches, and the signing-key lookup blocked the async event loop, so requests carrying invalid tokens could stall the single-worker instance and amplify traffic to the identity provider when ENABLE_OAUTH_BACKCHANNEL_LOGOUT was enabled. This issue is fixed in version 0.11.1.","ecosystems":["PyPI"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"weaponised"},"has_fix":true,"headline":"Open WebUI: Unauthenticated requests can stall the server via uncached OIDC fetches in back-channel logout","id":"CVE-2026-87011","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"PyPI","product":"openwebui:open_webui","products":["openwebui:open_webui"],"type":"denial_of_service","year":"2026"},"n_packages":3,"n_references":3,"next":{"headline":"Open WebUI: Any authenticated user can suppress calendar alerts instance-wide via a non-numeric alert value","id":"CVE-2026-87012"},"packages":[{"ecosystem":"PyPI","fixed":["0.11.1"],"introduced":["0.9.0"],"last_affected":[],"package":"open-webui","purl":null,"source":"GHSA-3g9q-v48f-hh9w"},{"ecosystem":"PyPI","fixed":["0.11.1"],"introduced":["0.9.0"],"last_affected":[],"package":"open-webui","purl":"pkg:pypi/open-webui","source":"GHSA-3g9q-v48f-hh9w"},{"ecosystem":"PyPI","fixed":["0.11.1"],"introduced":["0.9.0"],"last_affected":[],"package":"open-webui","purl":"pkg:pypi/open-webui","source":"PYSEC-2026-4117"}],"prev":{"headline":"Tugtainer: OIDC id_token claims accepted without signature/audience/expiry verification","id":"CVE-2026-87004"},"products":["open-webui"],"published":"2026-09-09","related":[{"cvss_score":9.1,"headline":"Open WebUI: LDAP Empty Password Authentication Bypass","id":"CVE-2026-44551","kev_date_added":null,"published":"2026-05-15"},{"cvss_score":9,"headline":"open-webui - Remote Code Execution via CORS Misconfiguration and Session Validation","id":"CVE-2026-56400","kev_date_added":null,"published":"2026-07-15"},{"cvss_score":9,"headline":"Cross-site Scripting (XSS) in open-webui/open-webui","id":"CVE-2024-8017","kev_date_added":null,"published":"2025-03-20"},{"cvss_score":8.8,"headline":"Open WebUI: Jupyter code execution works despite `ENABLE_CODE_EXECUTION=false` — feature gate bypassed","id":"CVE-2026-45672","kev_date_added":null,"published":"2026-05-15"},{"cvss_score":8.7,"headline":"Open WebUI: Same-origin XSS to account takeover via terminal port-preview iframe hardcoding allow-same-origin","id":"CVE-2026-87995","kev_date_added":null,"published":"2026-09-09"},{"cvss_score":8.7,"headline":"Open WebUI: Stored XSS via unescaped KaTeX render-error fallback in rendered messages","id":"CVE-2026-70492","kev_date_added":null,"published":"2026-08-04"},{"cvss_score":8.7,"headline":"Open WebUI: Stored XSS in Mermaid Markdown Preview","id":"CVE-2026-54011","kev_date_added":null,"published":"2026-06-23"}],"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":"CC BY 4.0","name":"PyPA Advisory Database","prefix":"PYSEC"},{"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":"yes","exploitation":"poc","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-09-14","vendors":["open-webui"]},"summary":"Unauthenticated attackers can cause denial of service in Open WebUI by sending invalid logout tokens that trigger uncached network fetches and block the event loop.","url":"https://insights.sbomify.com/CVE-2026-87011/"}