{"answers":{"affected":"It affects 1 product.","exploited":"Yes. Attackers have exploited CVE-2026-41091 in the wild since at least 20 May 2026.","fix":"No fix has been published for CVE-2026-41091 yet. Limit exposure of the affected software until one is available. US federal agencies must fix it by 3 Jun 2026.","what":"CVE-2026-41091 is a high-severity path traversal vulnerability in Microsoft Malware Protection Engine, published on 20 May 2026. It can only be exploited from the same machine or local network, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-41091 and fix it if it is affected.\n\nWhat it is: CVE-2026-41091 is a high-severity path traversal vulnerability in Microsoft Malware Protection Engine, published on 20 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.\nExploitation: Yes. Attackers have exploited CVE-2026-41091 in the wild since at least 20 May 2026.\n\nAffected product: Microsoft Malware Protection Engine. 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-2026-41091/ (Markdown: https://insights.sbomify.com/CVE-2026-41091/index.md)","id":"CVE-2026-41091","markdown":"https://insights.sbomify.com/CVE-2026-41091/index.md","name":"CVE-2026-41091","record":{"aliases":["GHSA-h776-j9jw-992p"],"analysis":{"component_type":"operating_system","fix_type":"patch","impacts":["privilege_escalation"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Microsoft Defender","requires_auth":"low_privilege","summary":"An authorized local attacker can elevate privileges by exploiting improper link resolution in Microsoft Defender.","user_interaction":"not_required","vuln_class":"path_traversal"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"microsoft","cpe":[{"product":"malware_protection_engine","vendor":"microsoft"}],"cvss":{"score":7.8,"severity":"high","source":"cna","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C","version":"3.1"},"cwes":[{"id":"CWE-59","name":"Improper Link Resolution Before File Access"}],"description":"Improper link resolution before file access ('link following') in Microsoft Defender allows an authorized attacker to elevate privileges locally.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":"2026-05-21","github_poc":4,"max_poc_stars":12,"metasploit":0,"nuclei":0,"refs":[{"date":"2026-05-21T19:16:25Z","kind":"github_poc","ref":"https://github.com/0xredash/CVE-2026-41091","stars":12,"title":"CVE-2026-41091"},{"date":"2026-06-20T10:25:34Z","kind":"github_poc","ref":"https://github.com/tc4dy/CVE-2026-41091-PoC-Exploit","stars":5,"title":"CVE-2026-41091 RedSun | Microsoft Defender LPE exploit. Low-privileged users gain NT AUTHORITY\\SYSTEM - via Cloud Files API + NTFS junction trickery. Forces Defender to write malicious payloads to System32 with SYSTEM rights - Actively exploited in wild. CVSS 7.8. Patch: Defender Engine 1.1.26040.8. Educational \u0026 Legal uses only."},{"date":"2026-08-09T11:23:46Z","kind":"github_poc","ref":"https://github.com/s4m98/RedSun-","stars":1,"title":"Windwos Zero Day Local PrivESc Exploit (CVE-2026-41091)"},{"date":"2026-05-22T23:42:50Z","kind":"github_poc","ref":"https://github.com/ridhinva/defender-privilege-escalation-scanner","stars":0,"title":"Scanner: CVE-2026-41091/45498 Microsoft Defender LPE/DoS — Python scanner for Windows Defender privilege escalation (CISA KEV)"}],"tier":"exploited"},"has_fix":null,"headline":"Microsoft Defender Link Following","id":"CVE-2026-41091","indexable":true,"kev":{"dateAdded":"2026-05-20","dueDate":"2026-06-03","knownRansomwareCampaignUse":"Unknown","product":"Defender","requiredAction":"Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.","vendorProject":"Microsoft","vulnerabilityName":"Microsoft Defender Link Following Vulnerability"},"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"path_traversal","year":"2026"},"n_packages":0,"n_references":1,"next":{"headline":"Microsoft Kinect Elevation of Privilege Vulnerability","id":"CVE-2026-41092"},"packages":[],"prev":{"headline":"Microsoft Copilot Tampering Vulnerability","id":"CVE-2026-41090"},"products":["Microsoft Malware Protection Engine"],"published":"2026-05-20","related":[{"cvss_score":9.3,"headline":"Memory corruption in n/a","id":"CVE-2013-1346","kev_date_added":null,"published":"2013-05-15"},{"cvss_score":8.1,"headline":"Microsoft Defender Remote Code Execution Vulnerability","id":"CVE-2026-45584","kev_date_added":null,"published":"2026-05-20"},{"cvss_score":7.8,"headline":"Microsoft Defender Elevation of Privilege Vulnerability","id":"CVE-2026-69414","kev_date_added":null,"published":"2026-08-14"},{"cvss_score":7.8,"headline":"Microsoft Defender Remote Code Execution Vulnerability","id":"CVE-2026-55011","kev_date_added":null,"published":"2026-07-14"},{"cvss_score":7.8,"headline":"Microsoft Defender Remote Code Execution Vulnerability","id":"CVE-2026-55012","kev_date_added":null,"published":"2026-07-14"},{"cvss_score":7.8,"headline":"Microsoft Defender Elevation of Privilege Vulnerability","id":"CVE-2026-50656","kev_date_added":null,"published":"2026-06-16"}],"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":"open","licence":"CC0 1.0","name":"CISA KEV"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"},{"class":"open","licence":"CC0","name":"PoC-in-GitHub"}],"ssvc":{"automatable":"no","exploitation":"active","technical_impact":"total"},"state":"PUBLISHED","updated":"2026-08-10","vendors":["Microsoft"]},"summary":"An authorized local attacker can elevate privileges by exploiting improper link resolution in Microsoft Defender.","url":"https://insights.sbomify.com/CVE-2026-41091/"}