CVE-2020-12049: An issue was discovered in dbus >= 1.3.0 before 1.12.18

Q: How do I fix CVE-2020-12049?

dbus: upgrade to 1.12.18; ubuntu linux: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.

Q: Is CVE-2020-12049 being exploited?

CVE-2020-12049 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2020-12049 affect?

CVE-2020-12049 affects dbus, ubuntu linux. Severity is medium (CVSS 5.5). An issue was discovered in dbus >= 1.3.0 before 1.12.18. The DBusServer in libdbus, as used in dbus-daemon, leaks file descriptors when a message exceeds the per-message file descriptor limit. A local attacker with access to the D-Bus syste

This month

MEDIUM 5.5WATCHLISTUPGRADEMITIGATE

CVE-2020-12049 is a medium-severity flaw (CVSS 5.5) affecting dbus, ubuntu linux. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

An issue was discovered in dbus >= 1.3.0 before 1.12.18. The DBusServer in libdbus, as used in dbus-daemon, leaks file descriptors when a message exceeds the per-message file descriptor limit. A local attacker with access to the D-Bus system bus or another system service's private AF_UNIX socket could use this to make the system service reach its file descriptor limit, denying service to subsequent D-Bus clients.

Why this priority

Public exploit reference
On your watchlist

A fixed release or distro patch exists.

Risk facts

CVSS score	5.5 (Medium)
Attack vector	Local
Attack complexity	Low
Privileges needed	Low
User interaction	None
EPSS exploit chance	0.6% (top 53%)
CISA exploited list	No
Weakness	CWE-404
Published	2020-06-08
Last modified	2026-06-17

Publisher (CNA): MITRE · Vendor: canonical · freedesktop

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2020-06-08 17:15 UTCPublished CVE record published
2026-06-17 02:51 UTCUpdated Record last modified

freedesktop dbus UPGRADE

Affected: >= 1.3.0 and < 1.12.18

Fixed in: 1.12.18

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy dbus || rpm -q dbus || dbus --version

2. UPGRADE to 1.12.18 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade dbus

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade dbus

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

canonical ubuntu linux MITIGATE

Affected: 12.04 · 14.04 · 16.04 · 18.04 · 19.10 · 20.04

Fixed in: no fixed release known

Safe to downgrade to: a release before 12.04

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2020-12049?

dbus: upgrade to 1.12.18; ubuntu linux: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2020-12049 being exploited?

CVE-2020-12049 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2020-12049 affect?

CVE-2020-12049 affects dbus, ubuntu linux. Severity is medium (CVSS 5.5). An issue was discovered in dbus >= 1.3.0 before 1.12.18. The DBusServer in libdbus, as used in dbus-daemon, leaks file descriptors when a message exceeds the per-message file descriptor limit. A local attacker with access to the D-Bus syste

How urgent is CVE-2020-12049?

Priority 41/100. Public exploit reference; On your watchlist

Software pages

Ubuntu vulnerabilities

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References

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