{"answers":{"affected":"3 open source packages ship an affected version, including github.com/fleetdm/fleet/v4. It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-26191 in the wild and no public exploit code.","fix":"Upgrade github.com/fleetdm/fleet/v4 to 4.81.1 or later.","what":"CVE-2026-26191 is a medium-severity command injection vulnerability in fleetdm fleet, published on 14 May 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-2026-26191 and fix it if it is affected.\n\nWhat it is: CVE-2026-26191 is a medium-severity command injection vulnerability in fleetdm fleet, published on 14 May 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-2026-26191 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- github.com/fleetdm/fleet/v4 (Go): affected all versions; fixed in 4.81.1\n- github.com/fleetdm/fleet/v4 (Go): affected all versions; fixed in 4.81.1\n- github.com/fleetdm/fleet/v4 (Go): affected all versions; fixed in 4.81.1\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-2026-26191/ (Markdown: https://insights.sbomify.com/CVE-2026-26191/index.md)","id":"CVE-2026-26191","markdown":"https://insights.sbomify.com/CVE-2026-26191/index.md","name":"CVE-2026-26191","record":{"aliases":["GHSA-9vcr-g537-3w5v","GO-2026-5301"],"analysis":{"component_type":"server_software","fix_type":"upgrade","impacts":["code_execution","privilege_escalation"],"network_reachable":"yes","non_default_config":false,"product_category":"Device management software","requires_auth":"none","summary":"Attackers can execute arbitrary commands as root or SYSTEM on managed endpoints by uploading crafted software packages with malicious metadata.","user_interaction":"required","vuln_class":"command_injection"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[{"product":"fleet","vendor":"fleetdm"}],"cvss":{"score":6,"severity":"medium","source":"cna","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N","version":"4.0"},"cwes":[{"id":"CWE-78","name":"Improper Neutralization of Special Elements used in an OS Command"}],"description":"Fleet is open source device management software. Prior to version 4.81.0, a vulnerability in Fleet's software installer pipeline could allow a crafted software package to execute arbitrary commands as root (macOS/Linux) or SYSTEM (Windows) on managed endpoints when an uninstall is triggered. When a software package (.pkg, .deb, .rpm, .exe, or .msi) is uploaded to Fleet, metadata is extracted from the package binary and used to generate uninstall scripts. In affected versions, this metadata is not properly sanitized before being included in the generated scripts. A specially crafted package containing malicious values in its metadata fields could result in unintended command execution when the uninstall script runs on managed endpoints. Version 4.81.0 contains a patch. If an immediate upgrade is not possible, administrators should avoid uploading software packages obtained from untrusted or unverified sources. Additionally, administrators can manually inspect and edit auto-generated uninstall scripts before deployment.","ecosystems":["Go"],"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":"Fleet vulnerable to OS command injection in software packages","id":"CVE-2026-26191","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"Go","product":null,"products":[],"type":"command_injection","year":"2026"},"n_packages":3,"n_references":2,"next":{"headline":"Open WebUI vulnerable to Stored XSS via iFrame in citations model","id":"CVE-2026-26192"},"packages":[{"ecosystem":"Go","fixed":["4.81.1"],"introduced":["0"],"last_affected":[],"package":"github.com/fleetdm/fleet/v4","purl":null,"source":"GHSA-9vcr-g537-3w5v"},{"ecosystem":"Go","fixed":["4.81.1"],"introduced":["0"],"last_affected":[],"package":"github.com/fleetdm/fleet/v4","purl":"pkg:golang/github.com/fleetdm/fleet/v4","source":"GHSA-9vcr-g537-3w5v"},{"ecosystem":"Go","fixed":["4.81.1"],"introduced":["0"],"last_affected":[],"package":"github.com/fleetdm/fleet/v4","purl":"pkg:golang/github.com/fleetdm/fleet/v4","source":"GO-2026-5301"}],"prev":{"headline":"Milvus Allows Unauthenticated Access to Restful API on Metrics Port (9091) Leads to Critical System Compromise","id":"CVE-2026-26190"},"products":["fleet"],"published":"2026-05-14","related":[{"cvss_score":10,"headline":"SAML authentication vulnerability in Fleet","id":"CVE-2020-26276","kev_date_added":null,"published":"2020-12-17"},{"cvss_score":9.3,"headline":"Fleet before 4.87.0 Authentication Bypass via Device Identifiers","id":"CVE-2026-103264","kev_date_added":null,"published":"2026-10-01"},{"cvss_score":9.3,"headline":"Fleet has a JWT signature bypass vulnerability in Azure AD MDM enrollment","id":"CVE-2026-23518","kev_date_added":null,"published":"2026-01-21"},{"cvss_score":8.7,"headline":"Fleet server may terminate unexpectedly when handling certain gRPC requests","id":"CVE-2026-26062","kev_date_added":null,"published":"2026-05-14"},{"cvss_score":8.7,"headline":"Fleet's unbounded request body read allows remote Denial of Service","id":"CVE-2026-26061","kev_date_added":null,"published":"2026-03-27"},{"cvss_score":8.2,"headline":"Fleet has a Windows MDM management endpoint authentication bypass","id":"CVE-2026-23998","kev_date_added":null,"published":"2026-05-14"},{"cvss_score":8.2,"headline":"Fleet Windows MDM Azure AD JWT Authentication Bypass","id":"CVE-2026-24899","kev_date_added":null,"published":"2026-05-14"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"GitHub Advisory Database","prefix":"GHSA"},{"class":"attribution","licence":"CC BY 4.0","name":"Go Vulnerability Database","prefix":"GO"},{"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":"2026-05-15","vendors":["fleetdm"]},"summary":"Attackers can execute arbitrary commands as root or SYSTEM on managed endpoints by uploading crafted software packages with malicious metadata.","url":"https://insights.sbomify.com/CVE-2026-26191/"}