{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-104721 in the wild and no public exploit code.","fix":"Upgrade to a fixed version.","what":"CVE-2026-104721 is a medium-severity path traversal vulnerability in QOS.CH Sarl Logback-classic, published on 2 Oct 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-2026-104721 and fix it if it is affected.\n\nWhat it is: CVE-2026-104721 is a medium-severity path traversal vulnerability in QOS.CH Sarl Logback-classic, published on 2 Oct 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-2026-104721 in the wild and no public exploit code.\n\nAffected product: QOS.CH Sarl Logback-classic. 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-2026-104721/ (Markdown: https://insights.sbomify.com/CVE-2026-104721/index.md)","id":"CVE-2026-104721","markdown":"https://insights.sbomify.com/CVE-2026-104721/index.md","name":"CVE-2026-104721","record":{"aliases":["DEBIAN-CVE-2026-104721","GHSA-5f86-rhcp-cxm6","UBUNTU-CVE-2026-104721","openSUSE-SU-2026:11985-1"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["data_modify"],"network_reachable":"yes","non_default_config":false,"product_category":"Java logging library","requires_auth":"none","summary":"Attackers can create or append log files outside intended directories by manipulating MDC values, affecting Java applications using Logback.","user_interaction":"not_required","vuln_class":"path_traversal"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"NCSC.ch","cpe":[],"cvss":{"score":6.3,"severity":"medium","source":"cna","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/S:P/AU:N/RE:M/U:Green","version":"4.0"},"cwes":[{"id":"CWE-22","name":"Improper Limitation of a Pathname to a Restricted Directory"}],"description":"Path-traversal vulnerability in QOS.CH Sarl Logback-classic on Java (logback-classic module) allows path-traversal vulnerability. More specifically, an \nMDC-based discriminator value flows unsanitized into a nested \nFileAppender path, letting an attacker who influences that MDC value \n(e.g. via an HTTP header)\n create and append log files outside the intended directory. \n\nThis issue affects Logback-classic: from 0.9.14 through 1.6.4.  This vulnerability is similar to CVE-2026-19880 but involves other attack techniques.","ecosystems":["openSUSE:Tumbleweed"],"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":"Logback: Incomplete protection against CVE-2026-19880","id":"CVE-2026-104721","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"path_traversal","year":"2026"},"n_packages":1,"n_references":1,"next":{"headline":"Path traversal in Listdom: AI-powered Business Directory with Classifieds Ads Listings","id":"CVE-2026-104722"},"packages":[{"ecosystem":"openSUSE:Tumbleweed","fixed":["1.6.5-2.1"],"introduced":["0"],"last_affected":[],"package":"logback","purl":"pkg:rpm/opensuse/logback\u0026distro=openSUSE%20Tumbleweed","source":"openSUSE-SU-2026:11985-1"}],"prev":{"headline":"Cifs-utils: mount.cifs credential-file option injection allows local privilege boundary bypass","id":"CVE-2026-104715"},"products":["Logback-classic"],"published":"2026-10-02","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"SUSE","prefix":"openSUSE"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2026-10-02","vendors":["QOS.CH Sarl"]},"summary":"Attackers can create or append log files outside intended directories by manipulating MDC values, affecting Java applications using Logback.","url":"https://insights.sbomify.com/CVE-2026-104721/"}