ubuntu

Common Problems 116594

Ubuntu 24.04 LTS – Certbot renewal fails with nginx authenticator errors – Fix & Prevention

🟠 High   ⏱ 5–30 min  Last verified: 26 October 2025 Affected versions: Ubuntu 24.04 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 116504

Ubuntu 24.04 LTS – secure boot blocks unsigned kernel module loading

🟠 High   ⏱ 5–30 min  Last verified: 26 October 2025 Affected versions: Ubuntu 24.04 LTS Ubuntu 24.04 Ubuntu 24.04.1 📖 ~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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Ubuntu 20.04 — linux-oracle-5.15 — multiple vulnerabilities (20 CVEs) — patch and remediation guide — diagnosis and fix on Ubuntu 20.04

Ubuntu 20.04 — linux-oracle-5.15 — multiple vulnerabilities (20 CVEs) — patch and remediation guide

🟠 High   ⏱ 15–60 min  Last verified: 25 October 2025 Affected versions: Ubuntu 20.04 (focal) 📖 ~4 min read  •  Source: Ubuntu Security Notice USN-8180-3 Related CVEs: CVE-2023-53421 CVE-2023-53520 CVE-2023-53662 CVE-2023-54207 CVE-2025-38057 CVE-2025-38125 CVE-2025-38232 CVE-2025-38408  +12 more Upstream summary: Several security issues were discovered in the Linux kernel. An attacker could possibly use these […]

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Ubuntu 24.04 — lambdaisland-uri-clojure — vulnerability — patch and remediation guide — diagnosis and fix on Ubuntu 24.04

Ubuntu 24.04 — lambdaisland-uri-clojure — vulnerability — patch and remediation guide

🟢 Low   ⏱ 5–15 min  Last verified: 25 October 2025 Affected versions: Ubuntu 24.04 (noble) 📖 ~4 min read  •  Source: Ubuntu Security Notice USN-8151-1 Related CVEs: CVE-2023-28628 Upstream summary: It was discovered that lambdaisland/uri did not properly sanitize the backslash character in URI strings. An attacker could possibly use this issue to bypass […]

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Common Problems 118432

Ubuntu 16.04 APT Lock File Prevents Package Updates

🟡 Medium   ⏱ 5–30 min  Last verified: 24 October 2025 📖 ~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 117053

Ubuntu 22.04 LTS – Apache fails to start because port 80 is already in use – Fix & Prevention

🟠 High   ⏱ 5–30 min  Last verified: 24 October 2025 Affected versions: Ubuntu 22.04 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 116627

Ubuntu 24.04 LTS – system time not syncing with NTP – Fix & Prevention

🟡 Medium   ⏱ 5–30 min  Last verified: 24 October 2025 Affected versions: Ubuntu 24.04 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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