Overview
Updated Intel microcode for Cherry + Bay Trial CPUs, fixes for
vulnerabilities in curl, Firefox, PHP and MariaDB, plus we talk
configuration of virtualised guests to mitigate speculative execution
vulnerabilities as well as plans for the Ubuntu 19.10 development cycle.
This week in Ubuntu Security Updates
[USN-3977-2] Intel Microcode update
4 CVEs addressed in Trusty ESM, Xenial, Bionic, Cosmic, DiscoCVE-2019-11091CVE-2018-12126CVE-2018-12127CVE-2018-12130Corresponding Intel microcode updates for Cherry Trail and Bay Trail CPU families[USN-3989-1] LibRaw vulnerabilities
7 CVEs addressed in Xenial, Bionic, CosmicCVE-2018-5819CVE-2018-5818CVE-2018-5817CVE-2018-20365CVE-2018-20364CVE-2018-20363CVE-2018-20337Multiple issues fixed:2*NULL pointer dereferenceHeap-based buffer overflowStack-based buffer overflow3 different cases of possible infinite loop - CPU DoS[USN-3990-1] urllib3 vulnerabilities
3 CVEs addressed in Xenial, Bionic, Cosmic, DiscoCVE-2019-11324CVE-2019-11236CVE-2018-20060When validating certs for HTTPS, could specify a set of certs to validateagainst - however it would always include the system CA certs as well -
so could validate successfully even if cert is not in chain of explicitly
desired set - fixed to NOT include system certs in this case
Possible CRLF injectionWould possibly expose HTTP authorization credentials across differentorigin hosts as after authenticating, if being redirected to a different
origin host, would still include the Authorization header from the old
host to the new host - fixed by ensuring this defaults to being off
[USN-3991-1] Firefox vulnerabilities
17 CVEs addressed in Xenial, Bionic, Cosmic, DiscoCVE-2019-9816CVE-2019-11698CVE-2019-11697CVE-2019-9821CVE-2019-9820CVE-2019-9819CVE-2019-9817CVE-2019-9814CVE-2019-9800CVE-2019-7317CVE-2019-11701CVE-2019-11699CVE-2019-11696CVE-2019-11695CVE-2019-11693CVE-2019-11692CVE-2019-11691Latest upstream Firefox release (67.0)Includes fixes for various issues including:DoS, spoofing of browser UI, tricking users into launching localexecutables, XSS and RCE
Tricking users into installing a malicious add-on by disabling the UI promptHistory exposure via bookmark handling[USN-3566-2] PHP vulnerabilities
5 CVEs addressed in Precise ESM, Trusty ESMCVE-2016-10712CVE-2017-11362CVE-2017-12933CVE-2019-11036CVE-2018-20783In February 2018, and March 2018, released updates for PHP5 in Trustyfixing multiple CVEs - this update is a corresponding update which fixes
some new CVEs in both Precise ESM and Trusty ESM and some of the same
older CVEs in Precise ESM.
[USN-3992-1] WebKitGTK+ vulnerabilities
3 CVEs addressed in Bionic, Cosmic, DiscoCVE-2019-8615CVE-2019-8607CVE-2019-8595New upstream release (2.24.2) - like most WebKitGTK+ updates, containslittle information on the new vulnerabilities - so assume the worst -
DoS, XSS, RCE
Used by GNOME Shell for captive portal handling etc[USN-3993-1, USN-3993-2] curl vulnerabilities
1 CVEs addressed in Precise ESM, Trusty ESM, Xenial, Bionic, Cosmic and DiscoCVE-2019-5436TFTP receive heap-based buffer overflow1 CVEs addressed in Xenial, Bionic, Cosmic, DiscoCVE-2019-5435Integer overflow for 32-bit arches when handling a very large URL (>2GB)via the libcurl API (curl_url_set())
[USN-3957-2] MariaDB vulnerabilities
2 CVEs addressed in Trusty ESMCVE-2019-2627CVE-2019-2614Episode 30 mentioned an update for MariaDB for the standard supportreleases fixing 8 CVEs - 2 of those applied to MariaDB in Trusty ESM -
both where a privileged attacker can crash server
Goings on in Ubuntu Security Community
Clarifications to documentation regarding latest Intel MDS vulnerabilities
https://wiki.ubuntu.com/SecurityTeam/KnowledgeBase/SpectreAndMeltdown/TechFAQUpdated to describe situation when doing virtualisation:To enable guest to mitigate various speculative executionvulnerabilities, need to ensure the guest CPU emulates the various CPU
features (such as pcid, ssbd etc).
Depends on workloads - if running untrusted code in guests or not etc.Previously QEMU would define various CPU models such as Broadwell-IBRSwhich would include support for this emulation. However, most of the
newer features ssbd, md_clear etc are not included in these CPU models.
So instead need to explicitly enable them - this can be done in a few ways:Can just passthrough host CPU features directly - recommendedapproach if NOT going to migrating guests across hosts (since if has
different features will cease to work)
Otherwise manually enable features directly as a subset of thesupported features from all the various hosts in your datacenter -
depending on whether using QEMU on the command-line or libvirt to
configure has different ways to specify this but same idea for both
Security Team plans for 19.10 development cycle
19.10 cycle roadmap meeting was held in Lyon a 2 weeks ago - each Ubuntuteam presented on the progress etc from the 19.04 cycle as well as their
plans for the 19.10 cycle
Security team highlights for 19.10:Automate more parts of our processes around triage of code reviews,reactive package updates etc
Review and incorporate KSPP recommendations for kernel hardeningGCC -fstack-clash-protection and -fcf-protection as defaultVarious snapd enhancements (daemon user, OpenGL support, audiomigration)
AppArmor features - prompting, more groundwork for fine-grained networkmediation
Hiring
Robotics Security Engineer
https://boards.greenhouse.io/canonical/jobs/1550997Security Certifications Engineer
https://boards.greenhouse.io/canonical/jobs/1660658Get in contact
#ubuntu-security on the Libera.Chat IRC network@ubuntu_sec on twitter