{ "CVE_data_meta": { "ASSIGNER": "security-advisories@github.com", "ID": "CVE-2021-41133", "STATE": "PUBLIC", "TITLE": "Sandbox bypass via recent VFS-manipulating syscalls" }, "affects": { "vendor": { "vendor_data": [ { "product": { "product_data": [ { "product_name": "flatpak", "version": { "version_data": [ { "version_value": ">= 1.8.0, <= 1.8.2" }, { "version_value": ">= 1.10.0, < 1.10.4" }, { "version_value": ">= 1.11.0, < 1.12.0" } ] } } ] }, "vendor_name": "flatpak" } ] } }, "data_format": "MITRE", "data_type": "CVE", "data_version": "4.0", "description": { "description_data": [ { "lang": "eng", "value": "Flatpak is a system for building, distributing, and running sandboxed desktop applications on Linux. In versions prior to 1.10.4 and 1.12.0, Flatpak apps with direct access to AF_UNIX sockets such as those used by Wayland, Pipewire or pipewire-pulse can trick portals and other host-OS services into treating the Flatpak app as though it was an ordinary, non-sandboxed host-OS process. They can do this by manipulating the VFS using recent mount-related syscalls that are not blocked by Flatpak's denylist seccomp filter, in order to substitute a crafted `/.flatpak-info` or make that file disappear entirely. Flatpak apps that act as clients for AF_UNIX sockets such as those used by Wayland, Pipewire or pipewire-pulse can escalate the privileges that the corresponding services will believe the Flatpak app has. Note that protocols that operate entirely over the D-Bus session bus (user bus), system bus or accessibility bus are not affected by this. This is due to the use of a proxy process `xdg-dbus-proxy`, whose VFS cannot be manipulated by the Flatpak app, when interacting with these buses. Patches exist for versions 1.10.4 and 1.12.0, and as of time of publication, a patch for version 1.8.2 is being planned. There are no workarounds aside from upgrading to a patched version." } ] }, "impact": { "cvss": { "attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 8.8, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "CHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H", "version": "3.1" } }, "problemtype": { "problemtype_data": [ { "description": [ { "lang": "eng", "value": "CWE-20: Improper Input Validation" } ] } ] }, "references": { "reference_data": [ { "name": "https://github.com/flatpak/flatpak/security/advisories/GHSA-67h7-w3jq-vh4q", "refsource": "CONFIRM", "url": "https://github.com/flatpak/flatpak/security/advisories/GHSA-67h7-w3jq-vh4q" }, { "name": "https://github.com/flatpak/flatpak/commit/1330662f33a55e88bfe18e76de28b7922d91a999", "refsource": "MISC", "url": "https://github.com/flatpak/flatpak/commit/1330662f33a55e88bfe18e76de28b7922d91a999" }, { "name": "https://github.com/flatpak/flatpak/commit/26b12484eb8a6219b9e7aa287b298a894b2f34ca", "refsource": "MISC", "url": "https://github.com/flatpak/flatpak/commit/26b12484eb8a6219b9e7aa287b298a894b2f34ca" }, { "name": "https://github.com/flatpak/flatpak/commit/462fca2c666e0cd2b60d6d2593a7216a83047aaf", "refsource": "MISC", "url": "https://github.com/flatpak/flatpak/commit/462fca2c666e0cd2b60d6d2593a7216a83047aaf" }, { "name": "https://github.com/flatpak/flatpak/commit/4c34815784e9ffda5733225c7d95824f96375e36", "refsource": "MISC", "url": "https://github.com/flatpak/flatpak/commit/4c34815784e9ffda5733225c7d95824f96375e36" }, { "name": "https://github.com/flatpak/flatpak/commit/89ae9fe74c6d445bb1b3a40e568d77cf5de47e48", "refsource": "MISC", "url": "https://github.com/flatpak/flatpak/commit/89ae9fe74c6d445bb1b3a40e568d77cf5de47e48" }, { "name": "https://github.com/flatpak/flatpak/commit/9766ee05b1425db397d2cf23afd24c7f6146a69f", "refsource": "MISC", "url": "https://github.com/flatpak/flatpak/commit/9766ee05b1425db397d2cf23afd24c7f6146a69f" }, { "name": "https://github.com/flatpak/flatpak/commit/a10f52a7565c549612c92b8e736a6698a53db330", "refsource": "MISC", "url": "https://github.com/flatpak/flatpak/commit/a10f52a7565c549612c92b8e736a6698a53db330" }, { "name": "https://github.com/flatpak/flatpak/commit/e26ac7586c392b5eb35ff4609fe232c52523b2cf", "refsource": "MISC", "url": "https://github.com/flatpak/flatpak/commit/e26ac7586c392b5eb35ff4609fe232c52523b2cf" }, { "refsource": "FEDORA", "name": "FEDORA-2021-4b201d15e6", "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/R5656ONDP2MGKIJMKEC7N2NXCV27WGTC/" }, { "refsource": "DEBIAN", "name": "DSA-4984", "url": "https://www.debian.org/security/2021/dsa-4984" }, { "refsource": "MLIST", "name": "[oss-security] 20211026 WebKitGTK and WPE WebKit Security Advisory WSA-2021-0006", "url": "http://www.openwall.com/lists/oss-security/2021/10/26/9" }, { "refsource": "FEDORA", "name": "FEDORA-2021-c5a9c85737", "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/T5DKCYRC6MFSTFCUP4DELCOUUP3SFEFX/" }, { "refsource": "GENTOO", "name": "GLSA-202312-12", "url": "https://security.gentoo.org/glsa/202312-12" } ] }, "source": { "advisory": "GHSA-67h7-w3jq-vh4q", "discovery": "UNKNOWN" } }