Common Problems

Debian 10 — python-pysaml2 — vulnerability — patch and remediation guide — diagnosis and fix on Debian 10

Debian 10 — python-pysaml2 — vulnerability — patch and remediation guide

🟢 Low   ⏱ 5–15 min  Last verified: 15 March 2021 Affected versions: Debian 10 (buster) 📖 ~4 min read  •  Source: Debian Security Tracker Related CVEs: CVE-2020-5390 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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openSUSE Tumbleweed — libdxflib — vulnerability — patch and remediation guide — diagnosis and fix on openSUSE Tumbleweed

openSUSE Tumbleweed — libdxflib — vulnerability — patch and remediation guide

🟠 High   ⏱ 15–60 min  Last verified: 25 May 2026 Affected versions: openSUSE Tumbleweed 📖 ~4 min read  •  Source: SUSE advisory openSUSE-SU-2022:0134-1 (see also SUSE bugzilla) Related CVEs: CVE-2021-21897 Upstream summary: A code execution vulnerability exists in the DL_Dxf::handleLWPolylineData functionality of Ribbonsoft dxflib 3.17.0. A specially-crafted .dxf file can lead to a heap […]

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Ubuntu 18.04 — junit4 — vulnerability — patch and remediation guide — diagnosis and fix on Ubuntu 18.04

Ubuntu 18.04 — junit4 — vulnerability — patch and remediation guide

🟢 Low   ⏱ 5–15 min  Last verified: 15 March 2021 Affected versions: Ubuntu 18.04 (bionic) 📖 ~4 min read  •  Source: Ubuntu Security Notice USN-4731-1 Related CVEs: CVE-2020-15250 Upstream summary: It was discovered that JUnit 4 contains a local information disclosure vulnerability. An attacker could possibly use this issue to obtain sensitive information. Table […]

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Arch Linux — lib32-libcurl-compat — multiple vulnerabilities (20 CVEs) — patch and remediation guide — diagnosis and fix on Arch Linux

Arch Linux — lib32-libcurl-compat — multiple vulnerabilities (20 CVEs) — patch and remediation guide

🔴 Critical   ⏱ 15–90 min  Last verified: 25 May 2026 Affected versions: Arch Linux (rolling release) 📖 ~4 min read  •  Source: Arch ASA ASA-201805-15 Related CVEs: CVE-2018-1000301 CVE-2018-1000300 CVE-2021-22901 CVE-2021-22898 CVE-2019-5436 CVE-2019-5435 CVE-2019-3823 CVE-2019-3822  +12 more Upstream summary: Type: multiple issues. Status: Fixed. Affected: 7.59.0-1. Fixed in: 7.60.0-1. Group: AVG-696. Table of contents […]

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Oracle Linux 8 — firefox — vulnerability — patch and remediation guide — diagnosis and fix on Oracle Linux 8

Oracle Linux 8 — firefox — vulnerability — patch and remediation guide (ELSA-2021-1360)

🟠 High   ⏱ 15–60 min  Last verified: 15 March 2021 Affected versions: Oracle Linux 8 📖 ~4 min read  •  Source: ELSA advisory ELSA-2021-1360 Related CVEs: CVE-2021-24002 CVE-2021-23998 CVE-2021-23994 CVE-2021-23995 CVE-2021-23999 CVE-2021-29945 Table of contents Symptom & Impact Environment & Reproduction Root Cause Analysis Quick Triage Step-by-Step Diagnosis Solution – Primary Fix Solution – […]

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

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

🟡 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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Common Problems 118002

UFW Blocks Expected Service Traffic

🟡 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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Common Problems 115636

firewalld Blocking Required Application Port – RHEL 7 Post 107

🟡 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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Common Problems 113415

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

🟡 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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