π ~4 min read β’ Source: Ubuntu Security Notice USN-3852-1
Related CVEs: CVE-2017-11591 CVE-2017-11683 CVE-2017-14859 CVE-2017-14862 CVE-2017-14864 CVE-2017-17669 CVE-2017-9239 CVE-2018-16336 +7 more
Upstream summary: It was discovered that Exiv2 incorrectly handled certain files.
An attacker could possibly use this issue to cause a denial of service.
CVE-2017-9239 only affected Ubuntu 14.04 LTS and Ubuntu 16.04 LTS.
(CVE-2017-11591, CVE-2017-11683, CVE-2017-14859, CVE-2017-14862,
CVE-2017-14864, CVE-2017-17669, CVE-2017-9239, CVE-2018-16336,
CVE-2018-1758)
Table of contents
Symptom & Impact
On Ubuntu 14.04 (trusty) hosts that have exiv2 installed, administrators report behaviour consistent with Ubuntu Security Notice USN-3852-1: apt reports pending security updates, services backed by exiv2 fail or restart unexpectedly, AppArmor denials appear in the kernel log, and β for security-rated advisories β the host is exposed to the vulnerability set above. Impact ranges from a single service-restart loop to wider availability incidents whenever exiv2 sits on the serving path.
Environment & Reproduction
Reproduction targets Ubuntu 14.04 (trusty). Confirm release and installed package:
lsb_release -a
cat /etc/os-release
dpkg -l exiv2 | tail -2
apt-cache policy exiv2
uname -r
Trigger the workflow that exposes exiv2 β multiple vulnerabilities (15 CVEs) β patch and remediation guide while collecting:
sudo tail -200 /var/log/syslog | grep -i exiv2
sudo tail -200 /var/log/syslog
sudo tail -200 /var/log/apt/history.log
sudo tail -200 /var/log/kern.log | grep -i apparmor
Root Cause Analysis
Root cause is documented in Ubuntu Security Notice USN-3852-1. Canonical security maintainers shipped fixes in the corresponding exiv2 update for Ubuntu 14.04; running an outdated build leaves the host exposed to the failure modes described in the advisory. On this release the fix typically arrives via the Ubuntu Pro ESM (esm-infra / esm-apps) channels rather than the standard archive. Correlate apt history with the journal:
grep -A2 -B2 exiv2 /var/log/apt/history.log
zgrep -A2 -B2 exiv2 /var/log/apt/history.log.*.gz 2>/dev/null
cat /proc/sys/kernel/tainted # non-zero = tainted kernel / out-of-tree modules
Quick Triage
Run these on Ubuntu 14.04 to capture the current state of exiv2:
dpkg -l exiv2 | tail -1 # installed version
dpkg -V exiv2 # verify shipped files
sudo apt update && apt list --upgradable 2>/dev/null | grep -i security
sudo service exiv2 status
sudo ufw status verbose 2>/dev/null | head -20
sudo aa-status 2>/dev/null | head -20
# If exiv2 ships a service unit (unit/job name often differs from pkg name, e.g.
# bind9βnamed, apache2βapache2, postgresql-NNβpostgresql@NN-main):
initctl list 2>/dev/null | grep exiv2
On trusty the standard archive no longer ships security fixes. Verify Ubuntu Pro ESM coverage:
# `pro` CLI not available on this release; check the older `ubuntu-advantage-tools`:
sudo ua status --format=json 2>/dev/null | head
apt-cache policy | grep -i esm
Step-by-Step Diagnosis
-
List failing services.
initctl list | grep -v running -
Tail the journal / syslog for
exiv2.sudo tail -f /var/log/upstart/exiv2.log sudo tail -f /var/log/syslog -
Inspect UFW (Uncomplicated Firewall) state.
sudo ufw status numbered sudo ufw show added sudo iptables -L -n -v | head -30 -
Surface AppArmor denials and switch the profile to complain mode if needed.
sudo journalctl -k 2>/dev/null | grep -i 'apparmor="DENIED"' | tail -30 sudo aa-status # /etc/apparmor.d/usr.bin.exiv2 or usr.sbin.exiv2 β inspect first sudo aa-complain /etc/apparmor.d/usr.bin.exiv2 2>/dev/null || true -
Verify
exiv2integrity and reinstall if anything is altered.sudo dpkg -V exiv2 sudo debsums -c exiv2 2>/dev/null sudo apt install --reinstall -y exiv2 -
Correlate findings with
/var/log/apt/history.log,/var/log/dpkg.log, and Ubuntu Security Notice USN-3852-1 to pin the change that introduced exiv2 β multiple vulnerabilities (15 CVEs) β patch and remediation guide.
Solution – Primary Fix
Apply the corrective apt transaction referenced by Ubuntu Security Notice USN-3852-1, then reload the affected service:
sudo apt update
sudo apt -y install --only-upgrade exiv2
# upstart uses initctl, not systemctl:
# Service name may differ from pkg name; check first:
initctl list 2>/dev/null | grep exiv2
sudo service exiv2 restart
dpkg -l exiv2 | tail -1 # confirm new version
sudo service exiv2 status
On trusty the standard archive is past EoL for security; enable Ubuntu Pro ESM to receive the fix:
# Older releases use the `ua` command:
sudo ua attach <token>
sudo ua enable esm-infra
sudo ua enable esm-apps
sudo apt update
sudo apt -y install --only-upgrade exiv2
For kernel / glibc / systemd / openssl advisories a reboot (or Livepatch) is required:
sudo apt install -y needrestart
sudo needrestart -r l # list units that need restart
sudo systemctl reboot # or: sudo shutdown -r now
Need help rolling this patch across an Ubuntu fleet? Our IT Solutions & Services team manages Ubuntu patch windows with Landscape and Ubuntu Pro integration. Get in touch for a free consultation.
Solution – Alternative Approaches
If the primary upgrade is not viable, pick from these:
-
Hold the package so apt cannot upgrade it:
sudo apt-mark hold exiv2 apt-mark showhold | grep exiv2 # Release the hold later with: sudo apt-mark unhold exiv2 -
Pin a known-good version via apt preferences:
# /etc/apt/preferences.d/exiv2.pref Package: exiv2 Pin: version <good-version> Pin-Priority: 1001 -
Downgrade to an older version if a regression is suspected:
apt-cache madison exiv2 sudo apt install --allow-downgrades -y exiv2=<older-version> -
Investigate AppArmor blocking the new binary; switch to complain briefly, capture denials, then re-enforce:
sudo aa-complain /etc/apparmor.d/usr.bin.exiv2 2>/dev/null # reproduce the failure sudo journalctl -k | grep apparmor | tail sudo aa-enforce /etc/apparmor.d/usr.bin.exiv2 2>/dev/null -
Take only the security pocket update and defer the full point-release upgrade:
sudo apt -y install --only-upgrade -t trusty-security exiv2
Verification & Acceptance Criteria
All of these should pass after the fix is applied:
dpkg -l exiv2 | tail -1 # expected fixed version
apt list --upgradable 2>/dev/null | grep -i security || echo OK
sudo service exiv2 status
sudo tail -50 /var/log/syslog | grep exiv2 || echo OK
sudo ufw status numbered | head
sudo aa-status 2>/dev/null | head -5
The original reproduction for exiv2 β multiple vulnerabilities (15 CVEs) β patch and remediation guide must not trigger across two consecutive runs.
Rollback Plan
Capture state before any change:
apt list --installed 2>/dev/null > /root/apt-pre.txt
dpkg --get-selections > /root/dpkg-pre.txt
# ZFS-on-root (Ubuntu 20.04+ default installer option):
sudo zfs snapshot rpool/ROOT/ubuntu@pre-exiv2
# LVM-on-root:
sudo lvcreate -L 4G -s -n root_pre_patch /dev/<vg>/<root-lv>
To revert:
sudo apt install --allow-downgrades -y exiv2=<old-version>
sudo service exiv2 restart
sudo service exiv2 restart
# Kernel rollback: pick the prior kernel from the GRUB menu, then:
sudo systemctl reboot
# ZFS rollback (rolls the whole root dataset):
sudo zfs rollback -r rpool/ROOT/ubuntu@pre-exiv2
Prevention & Hardening
Reduce the chance of this recurring on Ubuntu 14.04 (trusty):
-
Enable scheduled security updates via
unattended-upgrades:sudo apt install -y unattended-upgrades update-notifier-common sudo dpkg-reconfigure -plow unattended-upgrades # /etc/apt/apt.conf.d/50unattended-upgrades: Unattended-Upgrade::Allowed-Origins { "${distro_id}:${distro_codename}-security"; }; -
Install
needrestartso services restart automatically after library upgrades:sudo apt install -y needrestart # /etc/needrestart/needrestart.conf -> $nrconf{restart} = 'a'; -
Attach Ubuntu Pro for ESM (mandatory on this past-EoL release) and Livepatch where supported:
sudo ua attach <token> sudo ua enable esm-infra sudo ua enable esm-apps -
Subscribe to ubuntu-security-announce and watch ubuntu.com/security/cves.
-
Monitor file integrity with
debsumsand AIDE:sudo apt install -y debsums aide sudo debsums -ca sudo aideinit && sudo mv /var/lib/aide/aide.db.new /var/lib/aide/aide.db sudo aide --check -
For estate-wide patching, manage with Canonical Landscape:
sudo apt install -y landscape-client sudo landscape-config -
Keep AppArmor profiles in enforce mode and apply CIS Ubuntu Linux Benchmark hardening.
Related Errors & Cross-Refs
Issues that commonly surface alongside exiv2 β multiple vulnerabilities (15 CVEs) β patch and remediation guide: apt lock contention, broken dpkg state, systemd ordering cycles, AppArmor denials, and UFW rule drift. Useful triage:
sudo dpkg --configure -a
sudo apt --fix-broken install
initctl list | head
sudo journalctl -k 2>/dev/null | grep -i apparmor | tail
cat /proc/sys/kernel/tainted
View all ubuntu-14-04 tutorials on the Tutorials Hub →
Browse all common problems & solutions on the Tutorials Hub.
References & Further Reading
Primary reference: Ubuntu Security Notice USN-3852-1. Manual pages useful on Ubuntu 14.04:
man apt
man apt-get
man apt-mark
man dpkg
man initctl
# journald not present on this release
man ufw
man apparmor
man aa-status
man unattended-upgrades
man ua
Other resources: Ubuntu Security Notices, Ubuntu CVE Tracker, Ubuntu upgrade notes, and per-package notes in /usr/share/doc/exiv2/ for components implicated in exiv2 β multiple vulnerabilities (15 CVEs) β patch and remediation guide.