Security Hardening

Oracle Linux 8 — GNOME security, bug fix, and — enhancement update — new behaviour and fixes (ELSA-2020-4451)

• March 14, 2021
• Linux
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🟡 Medium   ⏱ 10–30 min  Last verified: 14 March 2021 Affected versions: Oracle Linux 8 📖 ~4 min read  •  Source: ELSA advisory ELSA-2020-4451 Related CVEs: CVE-2019-8846 CVE-2020-3897 CVE-2020-3900 CVE-2020-9895 CVE-2019-8813 CVE-2020-9806 Table of contents Symptom & Impact Environment & Reproduction Root Cause Analysis Quick Triage Step-by-Step Diagnosis Solution – Primary Fix Solution – […]

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UFW Blocks Expected Service Traffic

• March 14, 2021
• Tutorials
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🟡 Medium   ⏱ 5–30 min  Last verified: 14 March 2021 📖 ~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 References & Further […]

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firewalld Blocking Required Application Port – RHEL 7 Post 107

• March 14, 2021
• Tutorials
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🟡 Medium   ⏱ 5–30 min  Last verified: 14 March 2021 📖 ~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 References & Further […]

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How to Set Up a Static IP Address on SLES 12

• March 14, 2021
• SUSE Linux Enterprise
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Introduction This tutorial covers How to Set Up a Static IP Address on SLES 12 on SLES 12. SLES 12 (SUSE Linux Enterprise Server 16) is SUSE’s enterprise-grade Linux distribution. It uses the zypper package manager, AppArmor for mandatory access control, and systemctl for service management. Prerequisites Ensure your SLES 12 system is up to […]

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Amazon Linux 2 — lynis — multiple vulnerabilities (2 CVEs) — patch and remediation guide

• March 14, 2021
• Linux
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🟡 Medium   ⏱ 10–30 min  Last verified: 25 May 2026 Affected versions: Amazon Linux 2 📖 ~4 min read  •  Source: Amazon Linux advisory ALAS2LYNIS-2023-001 Related CVEs: CVE-2019-13033 CVE-2020-13882 Upstream summary: In CISOfy Lynis 2.x through 2.7.5, the license key can be obtained by looking at the process list when a data upload is […]

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Windows Server 2012 R2 — Split-brain DNS returns incorrect internal host records for hybrid workloads — Fix & Prevention

• March 14, 2021
• Tutorials
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🟡 Medium   ⏱ 5–30 min  Last verified: 14 March 2021 Affected versions: Windows Server 2012 R2 📖 ~2 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 […]

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Windows Server 2016 — WAS dependency chain breaks application pools — Fix & Prevention

• March 14, 2021
• Tutorials
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🟠 High   ⏱ 5–30 min  Last verified: 14 March 2021 Affected versions: Windows Server 2016 📖 ~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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Gentoo Linux — dev-php/PEAR-Archive_Tar — multiple vulnerabilities (4 CVEs) — patch and remediation guide

• March 14, 2021
• Linux
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🟡 Medium   ⏱ 10–30 min  Last verified: 25 May 2026 Affected versions: Gentoo Linux 📖 ~4 min read  •  Source: Gentoo GLSA GLSA-202101-23 Related CVEs: CVE-2020-28948 CVE-2020-28949 CVE-2020-36193 CVE-2018-1000888 Upstream summary: Multiple vulnerabilities have been discovered in PEAR Archive_Tar. Please review the CVE identifiers referenced below for details. Table of contents Symptom & Impact […]

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IBM AIX 7.1 — CVE-2021-29812 — xss — patch and remediation guide

• March 14, 2021
• Tutorials
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🟡 Medium   ⏱ 15–45 min  Last verified: 14 March 2021 Affected versions: IBM AIX 7.1 📖 ~4 min read  •  Source: NVD CVE-2021-29812, IBM Support Bulletin CVE: CVE-2021-29812 NVD summary: IBM Jazz for Service Management 1.1.3.10 and IBM Tivoli Netcool/OMNIbus_GUI is vulnerable to stored cross-site scripting. This vulnerability allows users to embed arbitrary JavaScript […]

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How to Configure Redis Sentinel on Oracle Linux 8

• March 14, 2021
• Oracle Linux
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Introduction This tutorial demonstrates how to Configure Redis Sentinel on Oracle Linux 8 on Oracle Linux 8. It is written for administrators who want a repeatable, well-explained walkthrough that goes beyond a bare command list and explains each configuration choice. Every command is tested against a freshly registered Oracle Linux 8 system with the default […]

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