CVE-2021-3493

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"http://packetstormsecurity.com/files/162866/Ubuntu-OverlayFS-Local-Privilege-Escalation.html"}, {"source": "security@ubuntu.com", "tags": ["Exploit", "Third Party Advisory", "VDB Entry"], "url": "http://packetstormsecurity.com/files/165151/Ubuntu-Overlayfs-Local-Privilege-Escalation.html"}, {"source": "security@ubuntu.com", "tags": ["Mailing List", "Patch", "Third Party Advisory"], "url": "https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7c03e2cda4a584cadc398e8f6641ca9988a39d52"}, {"source": "security@ubuntu.com", "tags": ["Vendor Advisory"], "url": "https://ubuntu.com/security/notices/USN-4917-1"}, {"source": "security@ubuntu.com", "tags": ["Mailing List", "Third Party Advisory"], "url": "https://www.openwall.com/lists/oss-security/2021/04/16/1"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Exploit", "Third Party Advisory", "VDB Entry"], "url": "http://packetstormsecurity.com/files/162434/Kernel-Live-Patch-Security-Notice-LSN-0076-1.html"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Press/Media Coverage", "Third Party Advisory", "VDB Entry"], "url": "http://packetstormsecurity.com/files/162866/Ubuntu-OverlayFS-Local-Privilege-Escalation.html"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Exploit", "Third Party Advisory", "VDB Entry"], "url": "http://packetstormsecurity.com/files/165151/Ubuntu-Overlayfs-Local-Privilege-Escalation.html"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Mailing List", "Patch", "Third Party Advisory"], "url": "https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7c03e2cda4a584cadc398e8f6641ca9988a39d52"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Vendor Advisory"], "url": "https://ubuntu.com/security/notices/USN-4917-1"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Mailing List", "Third Party Advisory"], "url": "https://www.openwall.com/lists/oss-security/2021/04/16/1"}, {"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "tags": ["US Government Resource"], "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-3493"}], "sourceIdentifier": "security@ubuntu.com", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-270"}], "source": "security@ubuntu.com", "type": "Secondary"}, {"description": [{"lang": "en", "value": "CWE-863"}], "source": "nvd@nist.gov", "type": "Primary"}]}

{"bugzilla": {"description": "kernel: overlayfs file system caps privilege escalation", "id": "1950506", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=1950506"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.4", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H", "status": "draft"}, "cwe": "CWE-552", "details": ["The overlayfs implementation in the linux kernel did not properly validate with respect to user namespaces the setting of file capabilities on files in an underlying file system. Due to the combination of unprivileged user namespaces along with a patch carried in the Ubuntu kernel to allow unprivileged overlay mounts, an attacker could use this to gain elevated privileges.", "A flaw was found in the Linux kernel. The overlayfs stacking file system does not properly validate the application of file capabilities against user namespaces. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability."], "name": "CVE-2021-3493", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:5", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 5"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel-alt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2021-04-16T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2021-3493\nhttps://nvd.nist.gov/vuln/detail/CVE-2021-3493\nhttps://www.cisa.gov/known-exploited-vulnerabilities-catalog"], "threat_severity": "Moderate"}

{}