Ubuntu 16.04

Common Problems 118458

Kernel Panic – not syncing: VFS

🟡 Medium   ⏱ 5–30 min  Last verified: 26 January 2020 📖 ~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 Enable SFTP Without Shell Access on Ubuntu 16.04 — step-by-step Linux tutorial on Progressive Robot

How To Enable SFTP Without Shell Access on Ubuntu 16.04

SFTP stands for SSH File Transfer Protocol. As its name suggests, it’s a secure way of transferring files to a server using an encrypted SSH connection. In a standard configuration, the SSH server grants file transfer access and terminal shell access to all users with an account on the system. In this tutorial, we’ll set up the SSH daemon to limit SFTP access to one directory with no SSH access allowed on per user basis.

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Common Problems 118409

Ubuntu 16.04 LTS DNS Resolution Intermittently Fails

🟡 Medium   ⏱ 5–30 min  Last verified: 23 January 2020 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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Ubuntu 16.04 — jackson-databind — multiple vulnerabilities (20 CVEs) — patch and remediation guide — diagnosis and fix on Ubuntu 16.04

Ubuntu 16.04 — jackson-databind — multiple vulnerabilities (20 CVEs) — patch and remediation guide

🟠 High   ⏱ 15–60 min  Last verified: 21 January 2020 Affected versions: Ubuntu 16.04 (xenial) 📖 ~4 min read  •  Source: Ubuntu Security Notice USN-4813-1 Related CVEs: CVE-2018-11307 CVE-2018-12022 CVE-2018-12023 CVE-2018-14718 CVE-2018-14719 CVE-2018-14720 CVE-2018-14721 CVE-2018-19360  +12 more Upstream summary: It was discovered that Jackson Databind incorrectly handled deserialization. An attacker could possibly use this […]

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Ubuntu 16.04 — fwupd — vulnerability — patch and remediation guide — diagnosis and fix on Ubuntu 16.04

Ubuntu 16.04 — fwupd — vulnerability — patch and remediation guide

🟢 Low   ⏱ 5–15 min  Last verified: 18 January 2020 Affected versions: Ubuntu 16.04 (xenial) 📖 ~4 min read  •  Source: Ubuntu Security Notice USN-4395-1 Related CVEs: CVE-2020-10759 Upstream summary: Justin Steven discovered that fwupd incorrectly handled certain signature verification. An attacker could possibly use this issue to install an unsigned firmware. Table of […]

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Common Problems 118428

Could Not Resolve security.ubuntu.com

🟡 Medium   ⏱ 5–30 min  Last verified: 15 January 2020 📖 ~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 118404

Ubuntu 16.04 LTS boot drops to initramfs after unclean shutdown

🟠 High   ⏱ 5–30 min  Last verified: 15 January 2020 Affected versions: 16.04 16.04.7 📖 ~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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How To Secure Roundcube on Ubuntu 16.04 — step-by-step Linux tutorial on Progressive Robot

How To Secure Roundcube on Ubuntu 16.04

In this tutorial, you’ll secure an existing basic Roundcube installation by adding SSL to Apache with Let’s Encrypt, adding two-factor authentication to your Roundcube account with a Roundcube plugin, and using GPG to sign and encrypt email with the Enigma plugin.

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Ubuntu 16.04 — libonig — multiple vulnerabilities (5 CVEs) — patch and remediation guide — diagnosis and fix on Ubuntu 16.04

Ubuntu 16.04 — libonig — multiple vulnerabilities (5 CVEs) — patch and remediation guide

🟡 Medium   ⏱ 10–30 min  Last verified: 9 January 2020 Affected versions: Ubuntu 16.04 (xenial) 📖 ~4 min read  •  Source: Ubuntu Security Notice USN-5662-1 Related CVEs: CVE-2019-16163 CVE-2019-19012 CVE-2019-19203 CVE-2019-19204 CVE-2019-19246 Upstream summary: It was discovered that Oniguruma incorrectly handled certain regular expressions. An attacker could possibly use this issue to cause a […]

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