{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-48991 in the wild and no public exploit code.","fix":"No fix has been published for CVE-2026-48991 yet. Limit exposure of the affected software until one is available.","what":"CVE-2026-48991 is a medium-severity authentication bypass vulnerability in XianYuLauncher, published on 17 Jun 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link."},"fix_prompt":"Check this codebase for CVE-2026-48991 and fix it if it is affected.\n\nWhat it is: CVE-2026-48991 is a medium-severity authentication bypass vulnerability in XianYuLauncher, published on 17 Jun 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.\nExploitation: There is no known exploitation of CVE-2026-48991 in the wild and no public exploit code.\n\nAffected product: XianYuLauncher. 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-2026-48991/ (Markdown: https://insights.sbomify.com/CVE-2026-48991/index.md)","id":"CVE-2026-48991","markdown":"https://insights.sbomify.com/CVE-2026-48991/index.md","name":"CVE-2026-48991","record":{"aliases":["GHSA-q6r9-qxmf-8hfx"],"analysis":{"component_type":"desktop_application","fix_type":"upgrade","impacts":["account_takeover"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Minecraft launcher","requires_auth":"none","summary":"Attackers can intercept local OAuth flows to steal authentication tokens and take over user accounts due to missing PKCE and state validation.","user_interaction":"required","vuln_class":"auth_bypass"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[],"cvss":{"score":5.5,"severity":"medium","source":"cna","vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N","version":"3.1"},"cwes":[{"id":"CWE-287","name":"Improper Authentication"}],"description":"XianYuLauncher is a Minecraft Java Edition launcher. In versions prior to 1.5.5, sensitive authentication artifacts could be exposed during a user-initiated login under certain local attack conditions. Affected versions relied on a fixed localhost redirect URI without PKCE or state validation. Exploitation is most likely to occur when an attacker is able to observe, intercept, or otherwise interfere with the local authentication flow on the same device. This issue has been fixed in version 1.5.5.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":false,"headline":"XianYuLauncher: Legacy Microsoft account OAuth sign-in flow lacks PKCE and state validation","id":"CVE-2026-48991","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"auth_bypass","year":"2026"},"n_packages":0,"n_references":2,"next":{"headline":"ImageMagick: Heap Buffer Over-Write in MAT decoder on 32-bit systems","id":"CVE-2026-48994"},"packages":[],"prev":{"headline":"joserfc: b64=false RFC7797 JWS payloads bypass JWSRegistry payload-size limits during deserialization","id":"CVE-2026-48990"},"products":["XianYuLauncher"],"published":"2026-06-17","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":"2026-06-18","vendors":["XianYuLauncher"]},"summary":"Attackers can intercept local OAuth flows to steal authentication tokens and take over user accounts due to missing PKCE and state validation.","url":"https://insights.sbomify.com/CVE-2026-48991/"}