📖 ~4 min read • Source: FreeBSD VuXML
VuXML topic: logstash — password disclosure vulnerability
Related CVEs: CVE-2014-3120 CVE-2014-4326 CVE-2015-4152 CVE-2015-5378
Upstream summary: Logstash developers report: Passwords Printed in Log Files under Some Conditions It was discovered that, in Logstash 2.1.0+, log messages generated by a stalled pipeline during shutdown will print plaintext contents of password fields. While investigating this issue we also discovered that debug logging has included this data for quite some time. Our latest releases fix both leaks. You will want to scrub old log files if this is of particular concern to you. This was fixed in
Table of contents
Symptom & Impact
On FreeBSD 12 hosts that have logstash installed, operators see behaviour consistent with the FreeBSD VuXML entry: pkg audit flags the installed version; any daemon, CLI tool, or application linked against logstash may misbehave or fail to start after upgrade; and — for security-rated advisories — the host is exposed to the vulnerabilities above. Impact ranges from a single restart cycle to full availability incidents on jails, bhyve guests, or downstream consumers that depend on logstash.
Environment & Reproduction
Reproduction targets FreeBSD 12. Confirm release, installed package, and capture baseline state:
freebsd-version -kru
uname -a
pkg info logstash
pkg query "%n-%v" logstash
pkg audit -F
service -e
Trigger the workflow that exposes logstash — multiple vulnerabilities (4 CVEs) — patch and remediation guide while collecting:
tail -200 /var/log/messages
dmesg -a | tail -200
tail -200 /var/log/pkg.log
Root Cause Analysis
Root cause is tracked at FreeBSD VuXML. The FreeBSD ports security team shipped a corrective logstash port revision; hosts on an outdated build remain exposed. Correlate package logs with system logs and kernel state to isolate the change that triggered the failure mode:
tail -500 /var/log/pkg.log
tail -500 /var/log/messages
sysctl kern.lastpid
sysctl kern.osreldate # numeric __FreeBSD_version, e.g. 1400097
Quick Triage
Run these checks on FreeBSD 12 to confirm the failure mode and current state of logstash:
pkg version -v logstash # installed vs available version
pkg audit logstash # advisory match for this package
tail -100 /var/log/messages
dmesg -a | tail -100
kldstat # kernel module state (for kernel/driver pkgs)
pfctl -sr 2>/dev/null || ipfw list # only if pf/ipfw is enabled
# If logstash ships an rc.d service (script name may differ from the pkg name,
# e.g. bind918→named, php83→php-fpm), check it:
service -e | grep -i logstash && service <rc-script-name> status
Step-by-Step Diagnosis
-
List enabled services (only relevant if the package provides one).
service -e -
Follow live logs.
tail -F /var/log/messages dmesg -
Validate firewall rules (skip if neither pf nor ipfw is enabled).
pfctl -sr -v 2>/dev/null || ipfw show -
Check package integrity for
logstash.pkg check -B logstash pkg check -d logstash # verify shared-library deps -
Reinstall
logstashif integrity check fails.pkg install -fy logstash -
Correlate findings with
/var/log/pkg.logand FreeBSD VuXML to pin the commit that introduced logstash — multiple vulnerabilities (4 CVEs) — patch and remediation guide.
Solution – Primary Fix
Install the corrective logstash port revision referenced by FreeBSD VuXML:
sudo pkg update
sudo pkg upgrade logstash # or: sudo pkg upgrade -y for the whole system
# If logstash provides an rc.d service, restart it (script name may differ from pkg name):
# sudo service <rc-script-name> restart
pkg audit logstash # confirm no remaining advisory for this package
For ports-tree builders (FreeBSD 13.x and earlier used portsnap; on FreeBSD 14+ the ports tree is fetched with Git):
# FreeBSD 14+ (portsnap was removed):
sudo pkg install -y git-lite
sudo git clone --depth 1 https://git.FreeBSD.org/ports.git /usr/ports
# FreeBSD 13.x and earlier:
# sudo portsnap fetch update
cd /usr/ports/<category>/logstash
sudo make deinstall reinstall clean
Reboot only if the package ships a kernel module or replaces a shared library used by long-running daemons.
Need help rolling this patch across a FreeBSD fleet? Our IT Solutions & Services team manages FreeBSD jail/bhyve patch windows. Get in touch for a free consultation.
Solution – Alternative Approaches
If the primary fix is not viable, choose from these alternatives:
-
Lock the package until the fix is vetted:
sudo pkg lock logstash -
Downgrade to a known-good revision.
pkg install pkgname-VERSIONis not a real downgrade syntax — fetch a specific build instead:# 1. Discover available versions across configured repos: pkg search -e logstash pkg rquery -r FreeBSD-quarterly '%n-%v' logstash # 2. Install from a specific saved .pkg file: sudo pkg add -f /path/to/logstash-<older-version>.pkg # 3. Or switch the host repo to the quarterly branch (see snippet below) and: sudo pkg upgrade -fr FreeBSD-quarterly logstash -
Switch the pkg repository between
quarterlyandlatestby editing/usr/local/etc/pkg/repos/FreeBSD.conf:FreeBSD: { url: "pkg+https://pkg.FreeBSD.org/${ABI}/quarterly", mirror_type: "srv", signature_type: "fingerprints", fingerprints: "/usr/share/keys/pkg", enabled: yes } -
Isolate the affected service in a jail with stricter firewall rules:
iocage create -n logstash-jail -r 12.4-RELEASE iocage set allow_raw_sockets=0 logstash-jail # or with Bastille: bastille create logstash-jail 12.4-RELEASE 10.0.0.10 -
Replace the service with a vendored static build for the period between exposure detection and full rollout.
Verification & Acceptance Criteria
All of these should pass after the fix:
pkg info logstash # shows the expected fixed version
pkg audit logstash # no advisory for this package (exit code 0)
tail -50 /var/log/messages # no new errors after upgrade
# If logstash ships a service, confirm it is running under its rc.d name:
# service <rc-script-name> status
The original reproduction for logstash — multiple vulnerabilities (4 CVEs) — patch and remediation guide must not trigger across two consecutive runs.
Rollback Plan
Capture state before any change (only ZFS root has boot environments — UFS hosts skip bectl):
pkg query "%n-%v" > /root/pkg-pre.txt
# ZFS-on-root only:
sudo bectl create pre-logstash-patch
To revert if the upgrade is bad, reinstall the previously saved .pkg file:
sudo pkg add -f /var/cache/pkg/logstash-<previous-version>.pkg
# Or activate the pre-patch boot environment and reboot (ZFS-on-root only):
sudo bectl activate pre-logstash-patch
sudo shutdown -r now
For kernel/loader changes on a UFS host, boot the previous kernel from the loader prompt (press 3 at the menu, then boot kernel.old).
Prevention & Hardening
Prevent recurrence on FreeBSD 12 hosts running logstash:
-
Enable the daily security pkg audit in
/etc/periodic.conf:daily_status_security_pkgaudit_enable="YES" -
Subscribe to
freebsd-security-notificationsat lists.freebsd.org. -
Mirror through a local pkg repository managed by
poudriere:poudriere jail -c -j 12amd64 -v 12.4-RELEASE poudriere ports -c -p default poudriere bulk -j 12amd64 -p default <category>/logstash -
Version-pin sensitive packages:
sudo pkg lock logstash -
Take an automatic ZFS boot-environment snapshot before every upgrade (ZFS root only):
sudo bectl create pre-upgrade-$(date +%Y%m%d) -
Monitor file integrity (create a baseline, verify against it later):
# Create a baseline (use -c; target /usr/local/etc, /etc, /boot — NOT /): sudo mtree -c -K sha256digest -p /usr/local/etc > /var/db/usr-local-etc.mtree sudo mtree -c -K sha256digest -p /etc > /var/db/etc.mtree # Verify later: sudo mtree -p /usr/local/etc < /var/db/usr-local-etc.mtree # Or with AIDE for a richer ruleset: sudo pkg install -y aide && sudo aide --init && sudo aide --check -
Harden jails with
allow.*tunables in/etc/jail.conf:logstash_jail { allow.raw_sockets = 0; allow.sysvipc = 0; allow.mount = 0; allow.chflags = 0; }
Related Errors & Cross-Refs
Issues that commonly surface alongside logstash — multiple vulnerabilities (4 CVEs) — patch and remediation guide: pkg lock contention, mismatched ABI after kernel/userland skew, pf rule drift, and stale shared-library references after upgrade. Triage with:
freebsd-version -kru
uname -K
pkg check -d
pfctl -sr
View all freebsd-12 tutorials on the Tutorials Hub →
Browse all common problems & solutions on the Tutorials Hub.
References & Further Reading
Primary reference: FreeBSD VuXML. Useful manual pages on FreeBSD 12:
man pkg
man freebsd-update
man pfctl
man ipfw
man bectl
man periodic.conf
Other resources: the FreeBSD Handbook, the FreeBSD Security Advisories at security.freebsd.org, and the /usr/ports/UPDATING file for port-specific notes implicated in logstash — multiple vulnerabilities (4 CVEs) — patch and remediation guide.