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pr cp 117582 r2

Ubuntu 20.04 LTS Failing TLS Due to Expired CA Bundle

🟠 High   ⏱ 5–30 min  Last verified: 20 May 2026 Affected versions: 20.04 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 12 — wolfssl — multiple vulnerabilities (20 CVEs) — patch and remediation guide — diagnosis and fix on Debian 12

Debian 12 — wolfssl — multiple vulnerabilities (20 CVEs) — patch and remediation guide

🟠 High   ⏱ 15–60 min  Last verified: 25 May 2026 Affected versions: Debian 12 (bookworm) 📖 ~4 min read  •  Source: Debian Security Tracker Related CVEs: CVE-2014-2901 CVE-2014-2902 CVE-2014-2903 CVE-2014-2904 CVE-2014-3566 CVE-2015-6925 CVE-2015-7744 CVE-2016-7438  +12 more Upstream summary: wolfssl before 3.2.0 does not properly issue certificates for a server's hostname. Table of contents Symptom […]

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pr cp 116082 r2

Ubuntu 26.04 LTS – apt update fails with NO_PUBKEY repository signature errors – Fix & Prevention

🟠 High   ⏱ 5–30 min  Last verified: 20 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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pr cp 111250 r2

Windows Server 2025 — wbadmin incremental backup consuming full disk due to change tracking reset — Fix & Prevention

🟡 Medium   ⏱ 5–30 min  Last verified: 20 May 2026 Affected versions: Windows Server 2025 📖 ~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 Errors […]

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pr cp 115579 r2

RHEL 7 sudo failures caused by PAM or sudoers syntax errors

🟠 High   ⏱ 5–30 min  Last verified: 20 May 2026 Affected versions: RHEL 7 📖 ~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 10 — zeromq3 — multiple vulnerabilities (2 CVEs) — patch and remediation guide — diagnosis and fix on Debian 10

Debian 10 — zeromq3 — multiple vulnerabilities (2 CVEs) — patch and remediation guide

🟢 Low   ⏱ 5–15 min  Last verified: 25 May 2026 Affected versions: Debian 10 (buster) 📖 ~4 min read  •  Source: Debian Security Tracker Related CVEs: CVE-2019-13132 CVE-2020-15166 Table of contents Symptom & Impact Environment & Reproduction Root Cause Analysis Quick Triage Step-by-Step Diagnosis Solution – Primary Fix Solution – Alternative Approaches Verification & […]

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Debian 9 — kamailio — multiple vulnerabilities (3 CVEs) — patch and remediation guide — diagnosis and fix on Debian 9

Debian 9 — kamailio — multiple vulnerabilities (3 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-2018-14767 CVE-2018-16657 CVE-2018-8828 Table of contents Symptom & Impact Environment & Reproduction Root Cause Analysis Quick Triage Step-by-Step Diagnosis Solution – Primary Fix Solution – Alternative Approaches Verification […]

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pr cp 114552 r2

Fail2ban Service Flapping Due to Invalid Jail Config

🟡 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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pr cp 118079 r2

Ubuntu 18.04 LTS UFW Rules Not Applied as Expected

🟡 Medium   ⏱ 5–30 min  Last verified: 20 May 2026 Affected versions: 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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pr cp 118569 r2

Ubuntu 16.04 LTS Drops to initramfs BusyBox on Boot

🟠 High   ⏱ 5–30 min  Last verified: 20 May 2026 Affected versions: 16.04 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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