{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-40017 in the wild and no public exploit code.","fix":"Upgrade to a fixed version.","what":"CVE-2026-40017 is a medium-severity denial of service vulnerability in Open-Xchange GmbH OX Dovecot CE, published on 28 Aug 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link."},"fix_prompt":"Check this codebase for CVE-2026-40017 and fix it if it is affected.\n\nWhat it is: CVE-2026-40017 is a medium-severity denial of service vulnerability in Open-Xchange GmbH OX Dovecot CE, published on 28 Aug 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.\nExploitation: There is no known exploitation of CVE-2026-40017 in the wild and no public exploit code.\n\nAffected product: Open-Xchange GmbH OX Dovecot CE. 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-2026-40017/ (Markdown: https://insights.sbomify.com/CVE-2026-40017/index.md)","id":"CVE-2026-40017","markdown":"https://insights.sbomify.com/CVE-2026-40017/index.md","name":"CVE-2026-40017","record":{"aliases":["ALPINE-CVE-2026-40017","AZL-98286","DEBIAN-CVE-2026-40017","GHSA-gr5f-599w-cg8j","UBUNTU-CVE-2026-40017"],"analysis":{"component_type":"server_software","fix_type":"upgrade","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"IMAP mail server","requires_auth":"none","summary":"An attacker can cause CPU exhaustion and denial of service in the IMAP THREAD command by sending crafted mail headers that collide in an internal hash table.","user_interaction":"required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"OX","cpe":[],"cvss":{"score":6.5,"severity":"medium","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","version":"3.1"},"cwes":[{"id":"CWE-400","name":"Uncontrolled Resource Consumption"}],"description":"An attacker that can send mail to a user can craft a message header whose values are chosen to collide in an internal hash table, which makes the IMAP THREAD command consume CPU disproportionate to the size of the message. This is a separate issue from CVE-2026-40014 and is not addressed by that fix. Whenever a mail client issues a THREAD command on the affected mailbox, this can cause degradation or denial of service for IMAP. Monitor system for abnormal CPU usage, kill the offending process and remove the offending message from the affected mailbox. Update to non-vulnerable version. No publicly available exploits are known.","ecosystems":[],"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":"Denial of service in OX Dovecot CE","id":"CVE-2026-40017","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"denial_of_service","year":"2026"},"n_packages":0,"n_references":1,"next":{"headline":"SQL injection in OX Dovecot CE","id":"CVE-2026-40018"},"packages":[],"prev":{"headline":"Denial of service in OX Dovecot Pro","id":"CVE-2026-40016"},"products":["OX Dovecot CE","OX Dovecot Pro"],"published":"2026-08-28","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":"partial"},"state":"PUBLISHED","updated":"2026-08-28","vendors":["Open-Xchange GmbH"]},"summary":"An attacker can cause CPU exhaustion and denial of service in the IMAP THREAD command by sending crafted mail headers that collide in an internal hash table.","url":"https://insights.sbomify.com/CVE-2026-40017/"}