{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-40854 in the wild and no public exploit code.","fix":"No fix has been published for CVE-2026-40854 yet. Limit exposure of the affected software until one is available.","what":"CVE-2026-40854 is a high-severity authentication bypass vulnerability in WNC T-Mobile 5G Box IDU, published on 16 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-40854 and fix it if it is affected.\n\nWhat it is: CVE-2026-40854 is a high-severity authentication bypass vulnerability in WNC T-Mobile 5G Box IDU, published on 16 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2026-40854 in the wild and no public exploit code.\n\nAffected product: WNC T-Mobile 5G Box IDU. 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-2026-40854/ (Markdown: https://insights.sbomify.com/CVE-2026-40854/index.md)","id":"CVE-2026-40854","markdown":"https://insights.sbomify.com/CVE-2026-40854/index.md","name":"CVE-2026-40854","record":{"aliases":["GHSA-7wq2-g42r-wr2h"],"analysis":{"component_type":"network_device","fix_type":"upgrade","impacts":["privilege_escalation","security_bypass"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"5G Box IDU router","requires_auth":"none","summary":"Attackers can bypass authentication on T-Mobile 5G Box IDU routers by manipulating session cookies to access the administration panel.","user_interaction":"not_required","vuln_class":"auth_bypass"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"CERT-PL","cpe":[],"cvss":{"score":8.7,"severity":"high","source":"cna","vector":"CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","version":"4.0"},"cwes":[{"id":"CWE-290","name":"Authentication Bypass by Spoofing"}],"description":"WNC T-Mobile 5G Box IDU router contains an authentication bypass vulnerability in the portal.cgi component. The session verification mechanism improperly validates the sessionid cookie by checking for the existence of a corresponding file in /tmp/login_user. An attacker can bypass authentication by using directory entries such as \".\" or \"..\" in the cookie, allowing unauthorized access to the administration panel.This issue has been fixed in firmware version 1.1.0.651412","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":null,"headline":"Session auth bypass via cookie value in T-Mobile 5G Box IDU routers","id":"CVE-2026-40854","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"auth_bypass","year":"2026"},"n_packages":0,"n_references":1,"next":{"headline":"Command Injection in T-Mobile 5G Box IDU router via ping functionality","id":"CVE-2026-40855"},"packages":[],"prev":{"headline":"Command injection via malicious configuration","id":"CVE-2026-40852"},"products":["T-Mobile 5G Box IDU"],"published":"2026-09-16","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":"no","exploitation":"none","technical_impact":"total"},"state":"PUBLISHED","updated":"2026-09-16","vendors":["WNC"]},"summary":"Attackers can bypass authentication on T-Mobile 5G Box IDU routers by manipulating session cookies to access the administration panel.","url":"https://insights.sbomify.com/CVE-2026-40854/"}