{"answers":{"affected":"It affects 2 products.","exploited":"There is no known exploitation of CVE-2021-21261 in the wild and no public exploit code.","fix":"Upgrade to a fixed version.","what":"CVE-2021-21261 is a high-severity code injection vulnerability in Debian Debian Linux, published on 14 Jan 2021. 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-2021-21261 and fix it if it is affected.\n\nWhat it is: CVE-2021-21261 is a high-severity code injection vulnerability in Debian Debian Linux, published on 14 Jan 2021. It can only be exploited from the same machine or local network, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2021-21261 in the wild and no public exploit code.\n\nAffected product: Debian Debian Linux. 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-2021-21261/ (Markdown: https://insights.sbomify.com/CVE-2021-21261/index.md)","id":"CVE-2021-21261","markdown":"https://insights.sbomify.com/CVE-2021-21261/index.md","name":"CVE-2021-21261","record":{"aliases":["CLEANSTART-2024-PO02295","DEBIAN-CVE-2021-21261","DSA-4830-1","GHSA-4ppf-fxf6-vxg2","OESA-2021-1043","RHSA-2021:0304","RHSA-2021:0306","RHSA-2021:0307","RHSA-2021:0411","SUSE-SU-2021:1094-1","UBUNTU-CVE-2021-21261","USN-4721-1","openSUSE-SU-2021:0520-1"],"analysis":{"component_type":"operating_system","fix_type":"upgrade","impacts":["code_execution","privilege_escalation"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Linux sandboxing tool","requires_auth":"low_privilege","summary":"A malicious Flatpak app can escape its sandbox and execute arbitrary code on the host system by manipulating environment variables passed to the portal service.","user_interaction":"not_required","vuln_class":"code_injection"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[{"product":"debian_linux","vendor":"debian"},{"product":"flatpak","vendor":"flatpak"}],"cvss":{"score":7.3,"severity":"high","source":"cna","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:N","version":"3.1"},"cwes":[{"id":"CWE-74","name":"Improper Neutralization of Special Elements in Output Used by a Downstream Component"}],"description":"Flatpak is a system for building, distributing, and running sandboxed desktop applications on Linux. A bug was discovered in the `flatpak-portal` service that can allow sandboxed applications to execute arbitrary code on the host system (a sandbox escape). This sandbox-escape bug is present in versions from 0.11.4 and before fixed versions 1.8.5 and 1.10.0. The Flatpak portal D-Bus service (`flatpak-portal`, also known by its D-Bus service name `org.freedesktop.portal.Flatpak`) allows apps in a Flatpak sandbox to launch their own subprocesses in a new sandbox instance, either with the same security settings as the caller or with more restrictive security settings. For example, this is used in Flatpak-packaged web browsers such as Chromium to launch subprocesses that will process untrusted web content, and give those subprocesses a more restrictive sandbox than the browser itself. In vulnerable versions, the Flatpak portal service passes caller-specified environment variables to non-sandboxed processes on the host system, and in particular to the `flatpak run` command that is used to launch the new sandbox instance. A malicious or compromised Flatpak app could set environment variables that are trusted by the `flatpak run` command, and use them to execute arbitrary code that is not in a sandbox. As a workaround, this vulnerability can be mitigated by preventing the `flatpak-portal` service from starting, but that mitigation will prevent many Flatpak apps from working correctly. This is fixed in versions 1.8.5 and 1.10.0.","ecosystems":["Red Hat:enterprise_linux:7::client","Red Hat:enterprise_linux:7::computenode","Red Hat:enterprise_linux:7::server","Red Hat:enterprise_linux:7::workstation","Red Hat:enterprise_linux:8::appstream","Red Hat:rhel_eus:8.1::appstream","Red Hat:rhel_eus:8.2::appstream","SUSE:Linux Enterprise Module for Basesystem 15 SP2","SUSE:Linux Enterprise Module for Desktop Applications 15 SP2","openSUSE:Leap 15.2"],"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":"Flatpak sandbox escape via spawn portal","id":"CVE-2021-21261","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"debian:debian_linux","products":["debian:debian_linux"],"type":"code_injection","year":"2021"},"n_packages":52,"n_references":8,"next":{"headline":"Query Binding Exploitation in Laravel","id":"CVE-2021-21263"},"packages":[{"ecosystem":"Red Hat:enterprise_linux:7::client","fixed":["0:1.0.9-10.el7_9"],"introduced":["0"],"last_affected":[],"package":"flatpak","purl":"pkg:rpm/redhat/flatpak","source":"RHSA-2021:0411"},{"ecosystem":"Red Hat:enterprise_linux:7::client","fixed":["0:1.0.0-10.el7_9"],"introduced":["0"],"last_affected":[],"package":"flatpak-builder","purl":"pkg:rpm/redhat/flatpak-builder","source":"RHSA-2021:0411"},{"ecosystem":"Red Hat:enterprise_linux:7::client","fixed":["0:1.0.9-10.el7_9"],"introduced":["0"],"last_affected":[],"package":"flatpak-debuginfo","purl":"pkg:rpm/redhat/flatpak-debuginfo","source":"RHSA-2021:0411"},{"ecosystem":"Red Hat:enterprise_linux:7::client","fixed":["0:1.0.9-10.el7_9"],"introduced":["0"],"last_affected":[],"package":"flatpak-devel","purl":"pkg:rpm/redhat/flatpak-devel","source":"RHSA-2021:0411"},{"ecosystem":"Red Hat:enterprise_linux:7::client","fixed":["0:1.0.9-10.el7_9"],"introduced":["0"],"last_affected":[],"package":"flatpak-libs","purl":"pkg:rpm/redhat/flatpak-libs","source":"RHSA-2021:0411"},{"ecosystem":"Red Hat:enterprise_linux:7::computenode","fixed":["0:1.0.9-10.el7_9"],"introduced":["0"],"last_affected":[],"package":"flatpak","purl":"pkg:rpm/redhat/flatpak","source":"RHSA-2021:0411"},{"ecosystem":"Red Hat:enterprise_linux:7::computenode","fixed":["0:1.0.0-10.el7_9"],"introduced":["0"],"last_affected":[],"package":"flatpak-builder","purl":"pkg:rpm/redhat/flatpak-builder","source":"RHSA-2021:0411"},{"ecosystem":"Red Hat:enterprise_linux:7::computenode","fixed":["0:1.0.9-10.el7_9"],"introduced":["0"],"last_affected":[],"package":"flatpak-debuginfo","purl":"pkg:rpm/redhat/flatpak-debuginfo","source":"RHSA-2021:0411"},{"ecosystem":"Red Hat:enterprise_linux:7::computenode","fixed":["0:1.0.9-10.el7_9"],"introduced":["0"],"last_affected":[],"package":"flatpak-devel","purl":"pkg:rpm/redhat/flatpak-devel","source":"RHSA-2021:0411"},{"ecosystem":"Red Hat:enterprise_linux:7::computenode","fixed":["0:1.0.9-10.el7_9"],"introduced":["0"],"last_affected":[],"package":"flatpak-libs","purl":"pkg:rpm/redhat/flatpak-libs","source":"RHSA-2021:0411"},{"ecosystem":"Red Hat:enterprise_linux:7::server","fixed":["0:1.0.9-10.el7_9"],"introduced":["0"],"last_affected":[],"package":"flatpak","purl":"pkg:rpm/redhat/flatpak","source":"RHSA-2021:0411"},{"ecosystem":"Red Hat:enterprise_linux:7::server","fixed":["0:1.0.0-10.el7_9"],"introduced":["0"],"last_affected":[],"package":"flatpak-builder","purl":"pkg:rpm/redhat/flatpak-builder","source":"RHSA-2021:0411"},{"ecosystem":"Red Hat:enterprise_linux:7::server","fixed":["0:1.0.9-10.el7_9"],"introduced":["0"],"last_affected":[],"package":"flatpak-debuginfo","purl":"pkg:rpm/redhat/flatpak-debuginfo","source":"RHSA-2021:0411"},{"ecosystem":"Red Hat:enterprise_linux:7::server","fixed":["0:1.0.9-10.el7_9"],"introduced":["0"],"last_affected":[],"package":"flatpak-devel","purl":"pkg:rpm/redhat/flatpak-devel","source":"RHSA-2021:0411"},{"ecosystem":"Red Hat:enterprise_linux:7::server","fixed":["0:1.0.9-10.el7_9"],"introduced":["0"],"last_affected":[],"package":"flatpak-libs","purl":"pkg:rpm/redhat/flatpak-libs","source":"RHSA-2021:0411"},{"ecosystem":"Red Hat:enterprise_linux:7::workstation","fixed":["0:1.0.9-10.el7_9"],"introduced":["0"],"last_affected":[],"package":"flatpak","purl":"pkg:rpm/redhat/flatpak","source":"RHSA-2021:0411"},{"ecosystem":"Red Hat:enterprise_linux:7::workstation","fixed":["0:1.0.0-10.el7_9"],"introduced":["0"],"last_affected":[],"package":"flatpak-builder","purl":"pkg:rpm/redhat/flatpak-builder","source":"RHSA-2021:0411"},{"ecosystem":"Red Hat:enterprise_linux:7::workstation","fixed":["0:1.0.9-10.el7_9"],"introduced":["0"],"last_affected":[],"package":"flatpak-debuginfo","purl":"pkg:rpm/redhat/flatpak-debuginfo","source":"RHSA-2021:0411"},{"ecosystem":"Red Hat:enterprise_linux:7::workstation","fixed":["0:1.0.9-10.el7_9"],"introduced":["0"],"last_affected":[],"package":"flatpak-devel","purl":"pkg:rpm/redhat/flatpak-devel","source":"RHSA-2021:0411"},{"ecosystem":"Red Hat:enterprise_linux:7::workstation","fixed":["0:1.0.9-10.el7_9"],"introduced":["0"],"last_affected":[],"package":"flatpak-libs","purl":"pkg:rpm/redhat/flatpak-libs","source":"RHSA-2021:0411"},{"ecosystem":"Red Hat:enterprise_linux:8::appstream","fixed":["0:1.6.2-5.el8_3"],"introduced":["0"],"last_affected":[],"package":"flatpak","purl":"pkg:rpm/redhat/flatpak","source":"RHSA-2021:0304"},{"ecosystem":"Red Hat:enterprise_linux:8::appstream","fixed":["0:1.6.2-5.el8_3"],"introduced":["0"],"last_affected":[],"package":"flatpak-debuginfo","purl":"pkg:rpm/redhat/flatpak-debuginfo","source":"RHSA-2021:0304"},{"ecosystem":"Red Hat:enterprise_linux:8::appstream","fixed":["0:1.6.2-5.el8_3"],"introduced":["0"],"last_affected":[],"package":"flatpak-debugsource","purl":"pkg:rpm/redhat/flatpak-debugsource","source":"RHSA-2021:0304"},{"ecosystem":"Red Hat:enterprise_linux:8::appstream","fixed":["0:1.6.2-5.el8_3"],"introduced":["0"],"last_affected":[],"package":"flatpak-libs","purl":"pkg:rpm/redhat/flatpak-libs","source":"RHSA-2021:0304"},{"ecosystem":"Red Hat:enterprise_linux:8::appstream","fixed":["0:1.6.2-5.el8_3"],"introduced":["0"],"last_affected":[],"package":"flatpak-libs-debuginfo","purl":"pkg:rpm/redhat/flatpak-libs-debuginfo","source":"RHSA-2021:0304"},{"ecosystem":"Red Hat:enterprise_linux:8::appstream","fixed":["0:1.6.2-5.el8_3"],"introduced":["0"],"last_affected":[],"package":"flatpak-selinux","purl":"pkg:rpm/redhat/flatpak-selinux","source":"RHSA-2021:0304"},{"ecosystem":"Red Hat:enterprise_linux:8::appstream","fixed":["0:1.6.2-5.el8_3"],"introduced":["0"],"last_affected":[],"package":"flatpak-session-helper","purl":"pkg:rpm/redhat/flatpak-session-helper","source":"RHSA-2021:0304"},{"ecosystem":"Red Hat:enterprise_linux:8::appstream","fixed":["0:1.6.2-5.el8_3"],"introduced":["0"],"last_affected":[],"package":"flatpak-session-helper-debuginfo","purl":"pkg:rpm/redhat/flatpak-session-helper-debuginfo","source":"RHSA-2021:0304"},{"ecosystem":"Red Hat:enterprise_linux:8::appstream","fixed":["0:1.6.2-5.el8_3"],"introduced":["0"],"last_affected":[],"package":"flatpak-tests-debuginfo","purl":"pkg:rpm/redhat/flatpak-tests-debuginfo","source":"RHSA-2021:0304"},{"ecosystem":"Red Hat:rhel_eus:8.1::appstream","fixed":["0:1.0.9-3.el8_1"],"introduced":["0"],"last_affected":[],"package":"flatpak","purl":"pkg:rpm/redhat/flatpak","source":"RHSA-2021:0306"},{"ecosystem":"Red Hat:rhel_eus:8.1::appstream","fixed":["0:1.0.9-3.el8_1"],"introduced":["0"],"last_affected":[],"package":"flatpak-debuginfo","purl":"pkg:rpm/redhat/flatpak-debuginfo","source":"RHSA-2021:0306"},{"ecosystem":"Red Hat:rhel_eus:8.1::appstream","fixed":["0:1.0.9-3.el8_1"],"introduced":["0"],"last_affected":[],"package":"flatpak-debugsource","purl":"pkg:rpm/redhat/flatpak-debugsource","source":"RHSA-2021:0306"},{"ecosystem":"Red Hat:rhel_eus:8.1::appstream","fixed":["0:1.0.9-3.el8_1"],"introduced":["0"],"last_affected":[],"package":"flatpak-libs","purl":"pkg:rpm/redhat/flatpak-libs","source":"RHSA-2021:0306"},{"ecosystem":"Red Hat:rhel_eus:8.1::appstream","fixed":["0:1.0.9-3.el8_1"],"introduced":["0"],"last_affected":[],"package":"flatpak-libs-debuginfo","purl":"pkg:rpm/redhat/flatpak-libs-debuginfo","source":"RHSA-2021:0306"},{"ecosystem":"Red Hat:rhel_eus:8.2::appstream","fixed":["0:1.6.2-4.el8_2"],"introduced":["0"],"last_affected":[],"package":"flatpak","purl":"pkg:rpm/redhat/flatpak","source":"RHSA-2021:0307"},{"ecosystem":"Red Hat:rhel_eus:8.2::appstream","fixed":["0:1.6.2-4.el8_2"],"introduced":["0"],"last_affected":[],"package":"flatpak-debuginfo","purl":"pkg:rpm/redhat/flatpak-debuginfo","source":"RHSA-2021:0307"},{"ecosystem":"Red Hat:rhel_eus:8.2::appstream","fixed":["0:1.6.2-4.el8_2"],"introduced":["0"],"last_affected":[],"package":"flatpak-debugsource","purl":"pkg:rpm/redhat/flatpak-debugsource","source":"RHSA-2021:0307"},{"ecosystem":"Red Hat:rhel_eus:8.2::appstream","fixed":["0:1.6.2-4.el8_2"],"introduced":["0"],"last_affected":[],"package":"flatpak-libs","purl":"pkg:rpm/redhat/flatpak-libs","source":"RHSA-2021:0307"},{"ecosystem":"Red Hat:rhel_eus:8.2::appstream","fixed":["0:1.6.2-4.el8_2"],"introduced":["0"],"last_affected":[],"package":"flatpak-libs-debuginfo","purl":"pkg:rpm/redhat/flatpak-libs-debuginfo","source":"RHSA-2021:0307"},{"ecosystem":"Red Hat:rhel_eus:8.2::appstream","fixed":["0:1.6.2-4.el8_2"],"introduced":["0"],"last_affected":[],"package":"flatpak-selinux","purl":"pkg:rpm/redhat/flatpak-selinux","source":"RHSA-2021:0307"}],"prev":{"headline":"XSS in description field","id":"CVE-2021-21260"},"products":["flatpak"],"published":"2021-01-14","related":[{"cvss_score":10,"headline":"ProFTPD Improper Access Control","id":"CVE-2015-3306","kev_date_added":"2026-10-08","published":"2015-05-18"},{"cvss_score":9.9,"headline":"RoundCube Webmail Deserialization of Untrusted Data","id":"CVE-2025-49113","kev_date_added":"2026-02-20","published":"2025-06-02"},{"cvss_score":9.8,"headline":"GNU InetUtils Argument Injection","id":"CVE-2026-24061","kev_date_added":"2026-01-26","published":"2026-01-21"},{"cvss_score":9.8,"headline":"Linux Kernel Improper Check for Unusual or Exceptional Conditions","id":"CVE-2025-39682","kev_date_added":"2026-09-18","published":"2025-09-05"},{"cvss_score":9.8,"headline":"Mozilla Firefox Use-After-Free","id":"CVE-2024-9680","kev_date_added":"2024-10-15","published":"2024-10-09"},{"cvss_score":9.8,"headline":"RARLAB UnRAR Directory Traversal","id":"CVE-2022-30333","kev_date_added":"2022-08-09","published":"2022-05-09"},{"cvss_score":9.8,"headline":"Roundcube Webmail SQL Injection","id":"CVE-2021-44026","kev_date_added":"2023-06-22","published":"2021-11-19"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"Red Hat","prefix":"RHSA"},{"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":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2024-08-03","vendors":["flatpak"]},"summary":"A malicious Flatpak app can escape its sandbox and execute arbitrary code on the host system by manipulating environment variables passed to the portal service.","url":"https://insights.sbomify.com/CVE-2021-21261/"}