{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-40686 in the wild and no public exploit code.","fix":"Upgrade to a fixed version.","what":"CVE-2026-40686 is a low-severity vulnerability in Exim Exim, published on 30 Apr 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-2026-40686 and fix it if it is affected.\n\nWhat it is: CVE-2026-40686 is a low-severity vulnerability in Exim Exim, published on 30 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2026-40686 in the wild and no public exploit code.\n\nAffected product: Exim Exim. 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-2026-40686/ (Markdown: https://insights.sbomify.com/CVE-2026-40686/index.md)","id":"CVE-2026-40686","markdown":"https://insights.sbomify.com/CVE-2026-40686/index.md","name":"CVE-2026-40686","record":{"aliases":["CLSA-2026-1778690918","CLSA-2026-1780519410","DEBIAN-CVE-2026-40686","GHSA-f965-ghfw-x6jx","UBUNTU-CVE-2026-40686"],"analysis":{"component_type":"server_software","fix_type":"upgrade","impacts":["data_read"],"network_reachable":"yes","non_default_config":true,"product_category":"Exim mail server","requires_auth":"none","summary":"An out-of-bounds read in Exim allows information disclosure via error messages when processing malformed UTF-8 headers with utf8 operators enabled.","user_interaction":"not_required","vuln_class":"information_disclosure"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"mitre","cpe":[{"product":"exim","vendor":"exim"}],"cvss":{"score":3.7,"severity":"low","source":"cna","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N","version":"3.1"},"cwes":[{"id":"CWE-125","name":"Out-of-bounds Read"}],"description":"In Exim before 4.99.2, when utf8 operators are enabled, there is an out-of-bounds read if large UTF-8 trailing characters are present (malformed UTF-8 header data). Information might be divulged within an error message produced during handling of an unrelated e-mail message.","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":"Information disclosure in Exim","id":"CVE-2026-40686","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"exim:exim","products":["exim:exim"],"type":"information_disclosure","year":"2026"},"n_packages":0,"n_references":4,"next":{"headline":"Memory corruption in Exim","id":"CVE-2026-40687"},"packages":[],"prev":{"headline":"Memory corruption in Exim","id":"CVE-2026-40685"},"products":["Exim"],"published":"2026-04-30","related":[{"cvss_score":9.8,"headline":"Use after free in Exim","id":"CVE-2026-45185","kev_date_added":null,"published":"2026-05-12"},{"cvss_score":9.8,"headline":"Exim AUTH Out-Of-Bounds Write Remote Code Execution Vulnerability","id":"CVE-2023-42115","kev_date_added":null,"published":"2024-05-03"},{"cvss_score":9.8,"headline":"Integer overflow in n/a","id":"CVE-2020-28017","kev_date_added":null,"published":"2021-05-06"},{"cvss_score":9.8,"headline":"Use after free in n/a","id":"CVE-2020-28018","kev_date_added":null,"published":"2021-05-06"},{"cvss_score":9.8,"headline":"Integer overflow in n/a","id":"CVE-2020-28020","kev_date_added":null,"published":"2021-05-06"},{"cvss_score":9.8,"headline":"Memory corruption in n/a","id":"CVE-2020-28022","kev_date_added":null,"published":"2021-05-06"},{"cvss_score":9.8,"headline":"Memory corruption in n/a","id":"CVE-2020-28024","kev_date_added":null,"published":"2021-05-06"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"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":"no","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-05-01","vendors":["Exim"]},"summary":"An out-of-bounds read in Exim allows information disclosure via error messages when processing malformed UTF-8 headers with utf8 operators enabled.","url":"https://insights.sbomify.com/CVE-2026-40686/"}