{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-103903 in the wild and no public exploit code.","fix":"No fix has been published for CVE-2026-103903 yet. Limit exposure of the affected software until one is available.","what":"CVE-2026-103903 is a high-severity authentication bypass vulnerability in MikroTik RouterOS, published on 12 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-103903 and fix it if it is affected.\n\nWhat it is: CVE-2026-103903 is a high-severity authentication bypass vulnerability in MikroTik RouterOS, published on 12 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2026-103903 in the wild and no public exploit code.\n\nAffected product: MikroTik RouterOS. 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-2026-103903/ (Markdown: https://insights.sbomify.com/CVE-2026-103903/index.md)","id":"CVE-2026-103903","markdown":"https://insights.sbomify.com/CVE-2026-103903/index.md","name":"CVE-2026-103903","record":{"aliases":["GHSA-23wm-v672-9cvc"],"analysis":{"component_type":"network_device","fix_type":"patch","impacts":["privilege_escalation","code_execution"],"network_reachable":"yes","non_default_config":false,"product_category":"MikroTik RouterOS","requires_auth":"low_privilege","summary":"Low-privilege WinBox users can bypass authentication checks to gain full administrative privileges on MikroTik RouterOS devices.","user_interaction":"not_required","vuln_class":"auth_bypass"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"ENISA","cpe":[],"cvss":{"score":8.7,"severity":"high","source":"cna","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","version":"4.0"},"cwes":[{"id":"CWE-863","name":"Incorrect Authorization"}],"description":"An incorrect authorization vulnerability in the WinBox\nauthentication flow of MikroTik RouterOS allows a remote authenticated attacker\nwith credentials for a low-privilege account permitted to use WinBox to obtain\nthe authorization policy of a different existing account. The stage-one EC-SRP\nchallenge and proof are verified using the attacker's account, while the\nindependently supplied stage-two username is used to install the target\naccount's privileges. By specifying a higher-privilege account such as admin, a\nlow-privilege user can obtain a full administrative session without knowing the\ntarget account's password and can use that session to increase the privileges\nof the attacker's own account.","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":"MikroTik RouterOS WinBox split-principal authentication bypass allows privilege escalation","id":"CVE-2026-103903","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"auth_bypass","year":"2026"},"n_packages":0,"n_references":4,"next":{"headline":"Stored XSS Vulnerability in JTL-Shop","id":"CVE-2026-103904"},"packages":[],"prev":{"headline":"DigiDoc improper signature verification","id":"CVE-2026-103902"},"products":["RouterOS"],"published":"2026-10-12","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":"2026-10-13","vendors":["MikroTik"]},"summary":"Low-privilege WinBox users can bypass authentication checks to gain full administrative privileges on MikroTik RouterOS devices.","url":"https://insights.sbomify.com/CVE-2026-103903/"}