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Rewterz Threat Advisory –Microsoft Windows Vulnerable to Privilege Escalation

July 21, 2021
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Rewterz Threat Advisory –Oracle Patches Critical Vulnerabilities

July 21, 2021

Rewterz Threat Advisory –New Linux kernel bug lets you get root on most modern distros

Severity

High

Analysis Summary

CVE-2021-33909

A size_t-to-int conversion vulnerability in the Linuxkernel’s filesystem layer: by creating, mounting, and deleting a deep directory structure whose total path length exceeds 1GB, an unprivileged local attacker can write the 10-byte string “//deleted” to an offset of exactly -2GB-10B below the beginning of a vmalloc()ated kernel buffer.

Impact

  • Full root privileges

Affected Vendors

Linux

Affected Products

  • All Linux kernel versions released since 2014

Remediation

Refer to Qualys advisory for the complete analysis and mitigation technique.

https://www.qualys.com/2021/07/20/cve-2021-33909/sequoia-local-privilege-escalation-linux.txt

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