{
  "cveId": "CVE-2021-20321",
  "url": "https://patchblox.com/security/cve/CVE-2021-20321",
  "summary": "CVE-2021-20321 is fixed in 38 products on 1 platform, first by RHSA-2021:5227, released December 21, 2021. It is not reported as exploited. Patch Radar priority: Routine.",
  "title": "bpftool: The kernel packages contain the Linux kernel, the core of any Linux operating system.\n\nSecurity Fix(es):\n\n* kernel: I...",
  "description": "The kernel packages contain the Linux kernel, the core of any Linux operating system.\n\nSecurity Fix(es):\n\n* kernel: In Overlayfs missing a check for a negative dentry before calling vfs_rename() (CVE-2021-20321)\n\nFor more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.\n\nBug Fix(es):\n\n* panic while breaking a lease/delegation after user mode helper invocation (BZ#2010333)\n\n* The ASR driver is causing a system crash in RHEL8.4 compared to RHEL8.3 due to kernel changes (BZ#2016384)\n\n* RHEL8: DFS provided SMB shares are not accessible following unprivileged access (BZ#2017177)\n\n* Avoid hitting the rtnl_trylock/restart_syscall logic in net-sysfs when possible (BZ#2021165)\n\n* RHEL8: x86/Kconfig: Do not enable AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT (BZ#2024678)\n\n* RHEL8.4-[Regression][P10][DD2.0][Rainier/Denali] - system crashed while offlining and onlining cores (BZ#2026450)",
  "published": "2021-12-21T00:00:00Z",
  "severity": "Moderate",
  "cvss": 5.5,
  "cvssVector": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H",
  "epss": 0.00216,
  "epssPercentile": 0.12081,
  "priority": "Routine",
  "priorityTier": 4,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
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