Linux

Debian 10 — dovecot — multiple vulnerabilities (4 CVEs) — patch and remediation guide — diagnosis and fix on Debian 10

Debian 10 — dovecot — multiple vulnerabilities (4 CVEs) — patch and remediation guide

🟡 Medium   ⏱ 10–30 min  Last verified: 25 May 2026 Affected versions: Debian 10 (buster) 📖 ~4 min read  •  Source: Debian Security Tracker Related CVEs: CVE-2019-11500 CVE-2020-10957 CVE-2020-12100 CVE-2020-24386 Table of contents Symptom & Impact Environment & Reproduction Root Cause Analysis Quick Triage Step-by-Step Diagnosis Solution – Primary Fix Solution – Alternative Approaches […]

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Oracle Linux 9 — .NET 9.0 security, bug fix, and — enhancement update — new behaviour and fixes — diagnosis and fix on Oracle Linux 9

Oracle Linux 9 — .NET 9.0 security, bug fix, and — enhancement update — new behaviour and fixes

🟠 High   ⏱ 15–60 min  Last verified: 25 May 2026 Affected versions: Oracle Linux 9 📖 ~4 min read  •  Source: ELSA advisory ELSA-2025-2668 Related CVEs: CVE-2025-24070 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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Debian 11 — curl — multiple vulnerabilities (20 CVEs) — patch and remediation guide — diagnosis and fix on Debian 11

Debian 11 — curl — multiple vulnerabilities (20 CVEs) — patch and remediation guide

🟠 High   ⏱ 15–60 min  Last verified: 25 May 2026 Affected versions: Debian 11 (bullseye) 📖 ~4 min read  •  Source: Debian Security Tracker Related CVEs: CVE-2003-1605 CVE-2005-0490 CVE-2005-3185 CVE-2005-4077 CVE-2006-1061 CVE-2007-3564 CVE-2009-0037 CVE-2009-2417  +12 more Upstream summary: curl 7.x before 7.10.7 sends CONNECT proxy credentials to the remote server. Table of contents Symptom […]

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Common Problems 115538

RHEL 7 firewalld Rich Rule Order Breaks DNAT

🟡 Medium   ⏱ 5–30 min  Last verified: 20 May 2026 📖 ~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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SLES 12 — grub2 — multiple vulnerabilities (20 CVEs) — patch and remediation guide — diagnosis and fix on SLES 12

SLES 12 — grub2 — multiple vulnerabilities (20 CVEs) — patch and remediation guide

🟠 High   ⏱ 15–60 min  Last verified: 25 May 2026 Affected versions: SLES 12 📖 ~4 min read  •  Source: SUSE advisory ESSA-2025:2835 (see also SUSE bugzilla) Related CVEs: CVE-2024-56737 CVE-2025-0624 CVE-2023-4692 CVE-2021-3695 CVE-2021-3697 CVE-2022-28733 CVE-2022-28734 CVE-2022-28736  +12 more Upstream summary: GNU GRUB (aka GRUB2) through 2.12 has a heap-based buffer overflow in fs/hfs.c […]

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SLES 16 — npm22 — multiple vulnerabilities (19 CVEs) — patch and remediation guide — diagnosis and fix on SLES 16

SLES 16 — npm22 — multiple vulnerabilities (19 CVEs) — patch and remediation guide

🟠 High   ⏱ 15–60 min  Last verified: 25 May 2026 Affected versions: SLES 16 📖 ~4 min read  •  Source: SUSE advisory RHSA-2026:1842 (see also SUSE bugzilla) Related CVEs: CVE-2025-55130 CVE-2025-55131 CVE-2025-59465 CVE-2025-23083 CVE-2025-23166 CVE-2025-59466 CVE-2026-21637 CVE-2026-22036  +11 more Upstream summary: A flaw in Node.js's Permissions model allows attackers to bypass `–allow-fs-read` and `–allow-fs-write` […]

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Common Problems 115022

RHEL 8 Subscription-Manager Shows Repositories Disabled Unexpectedly

🟠 High   ⏱ 5–30 min  Last verified: 19 May 2026 Affected versions: 8.4 8.5 8.6 8.7 8.8 8.9 8.10 📖 ~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 […]

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Common Problems 118036

Ubuntu 18.04 LTS – SSH key authentication fails due to permission errors – Fix & Prevention

🟠 High   ⏱ 5–30 min  Last verified: 19 May 2026 Affected versions: Ubuntu 18.04 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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Common Problems 119062

Ubuntu 14.04 LTS UFW rule change accidentally blocks SSH

🔴 Critical   ⏱ 5–30 min  Last verified: 19 May 2026 Affected versions: 14.04 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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Debian 9 — roundcube — multiple vulnerabilities (5 CVEs) — patch and remediation guide — diagnosis and fix on Debian 9

Debian 9 — roundcube — multiple vulnerabilities (5 CVEs) — patch and remediation guide

🟡 Medium   ⏱ 10–30 min  Last verified: 25 May 2026 Affected versions: Debian 9 (stretch) 📖 ~4 min read  •  Source: Debian Security Tracker Related CVEs: CVE-2017-16651 CVE-2018-19206 CVE-2018-9846 CVE-2020-12625 CVE-2020-13964 Table of contents Symptom & Impact Environment & Reproduction Root Cause Analysis Quick Triage Step-by-Step Diagnosis Solution – Primary Fix Solution – Alternative […]

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