Linux

Ubuntu 20.04 — node-tar — vulnerability — patch and remediation guide — diagnosis and fix on Ubuntu 20.04

Ubuntu 20.04 — node-tar — vulnerability — patch and remediation guide

🟢 Low   ⏱ 5–15 min  Last verified: 25 May 2026 Affected versions: Ubuntu 20.04 (focal) 📖 ~4 min read  •  Source: Ubuntu Security Notice USN-5283-1 Related CVEs: CVE-2021-32803 Upstream summary: It was discovered that Tar for Node.js did not properly sanitize path inputs. An attacker could possibly use this issue to read arbitrary files, […]

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How To Manage RAID Arrays with mdadm on Ubuntu 16.04 — step-by-step Linux tutorial on Progressive Robot

How To Manage RAID Arrays with mdadm on Ubuntu 16.04

In this guide, we discuss how to use Linux’s mdadm utility to manage RAID arrays and perform day-to-day administrative tasks. We cover how to start, stop, or remove RAID arrays, how to find information about both the RAID device and the underlying storage components, and how to adjust the RAID size and and hot spares to existing arrays.

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How to Install and Configure cAdvisor for Container Monitoring on RHEL 7 — step-by-step RHEL 7 tutorial on Progressive Robot

How to Install and Configure cAdvisor for Container Monitoring on RHEL 7

How to Install and Configure cAdvisor for Container Monitoring on RHEL 7 cAdvisor (Container Advisor) is an open-source agent developed by Google that collects, aggregates, processes, and exports resource usage and performance metrics for running containers. It provides a real-time web UI and a Prometheus-compatible metrics endpoint, making it the standard solution for container observability […]

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How To Harden OpenSSH Client on Ubuntu 20.04 — step-by-step Linux tutorial on Progressive Robot

How To Harden OpenSSH Client on Ubuntu 20.04

When hardening SSH at the server side, the primary objective is to make it harder for malicious actors to access your server. However, hardening at the client side is very different, as instead you are working to defend and protect your SSH connection and client from various different threats. In this tutorial, you will harden your Ubuntu 20.04 OpenSSH client in order to help ensure that outgoing SSH connections are as secure as possible.

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Oracle Linux 8 — qt5 security, bug fix, and — enhancement update — new behaviour and fixes — diagnosis and fix on Oracle Linux 8

Oracle Linux 8 — qt5 security, bug fix, and — enhancement update — new behaviour and fixes (ELSA-2022-7482)

🟡 Medium   ⏱ 10–30 min  Last verified: 25 May 2026 Affected versions: Oracle Linux 8 📖 ~4 min read  •  Source: ELSA advisory ELSA-2022-7482 Related CVEs: CVE-2022-25255 Table of contents Symptom & Impact Environment & Reproduction Root Cause Analysis Quick Triage Step-by-Step Diagnosis Solution – Primary Fix Solution – Alternative Approaches Verification & Acceptance […]

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Gentoo Linux — media-libs/lib3mf — vulnerability — patch and remediation guide — diagnosis and fix on Gentoo Linux

Gentoo Linux — media-libs/lib3mf — vulnerability — patch and remediation guide

🟡 Medium   ⏱ 10–30 min  Last verified: 25 May 2026 Affected versions: Gentoo Linux 📖 ~4 min read  •  Source: Gentoo GLSA GLSA-202208-01 Related CVEs: CVE-2021-21772 Upstream summary: Incorrect memory handling within lib3mf could result in a use-after-free. Table of contents Symptom & Impact Environment & Reproduction Root Cause Analysis Quick Triage Step-by-Step Diagnosis […]

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Common Problems 119131

Ubuntu 14.04 LTS CIFS mount authentication fails after password rotation

🟡 Medium   ⏱ 5–30 min  Last verified: 20 May 2026 Affected versions: 14.04 📖 ~1 min read Table of contents Symptom & Impact Environment & Reproduction Root Cause Analysis Quick Triage Step-by-Step Diagnosis Solution – Primary Fix Solution – Alternative Approaches Verification & Acceptance Criteria Rollback Plan Prevention & Hardening Related Errors & Cross-Refs […]

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Common Problems 115912

Ubuntu 26.04 LTS – apt upgrade blocked by held packages – Fix & Prevention

🟡 Medium   ⏱ 5–30 min  Last verified: 19 May 2026 Affected versions: Ubuntu 26.04 LTS 📖 ~1 min read Table of contents Symptom & Impact Environment & Reproduction Root Cause Analysis Quick Triage Step-by-Step Diagnosis Solution – Primary Fix Solution – Alternative Approaches Verification & Acceptance Criteria Rollback Plan Prevention & Hardening Related Errors […]

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How To Write Custom System Audit Rules on CentOS 7 — step-by-step Linux tutorial on Progressive Robot

How To Write Custom System Audit Rules on CentOS 7

The Linux Audit System creates an audit trail, a way to track all kinds of information on your system. It can record a lot of data like types of events, the date and time, user IDs, system calls, processes, files used, SELinux contexts, and sensitivity levels. It can track whether a file has been accessed, edited, or executed. It can even track if changes to file attributes.

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Ubuntu 14.04 — pcre3 — multiple vulnerabilities (20 CVEs) — patch and remediation guide — diagnosis and fix on Ubuntu 14.04

Ubuntu 14.04 — pcre3 — multiple vulnerabilities (20 CVEs) — patch and remediation guide

🟠 High   ⏱ 15–60 min  Last verified: 25 May 2026 Affected versions: Ubuntu 14.04 (trusty) 📖 ~4 min read  •  Source: Ubuntu Security Notice USN-5425-1 Related CVEs: CVE-2019-20838 CVE-2020-14155 CVE-2014-9769 CVE-2015-2325 CVE-2015-2326 CVE-2015-2327 CVE-2015-2328 CVE-2015-3210  +12 more Upstream summary: Yunho Kim discovered that PCRE incorrectly handled memory when handling certain regular expressions. An attacker […]

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