CVE-2016-7795

systemd: Assertion failure when PID 1 receives a zero-length message over notify socket

Severity Score

5.5

*CVSS v3

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

The manager_invoke_notify_message function in systemd 231 and earlier allows local users to cause a denial of service (assertion failure and PID 1 hang) via a zero-length message received over a notify socket.

La función manager_invoke_notify_message en systemd 231 y versiones anteriores permite a usuarios locales provocar una denegación de servicio (fallo de afirmación y colgado de PID 1) a través de un mensaje de longitud cero recibido sobre una notificación de encaje.

A flaw was found in the way systemd handled empty notification messages. A local attacker could use this flaw to make systemd freeze its execution, preventing further management of system services, system shutdown, or zombie process collection via systemd.

The systemd packages contain systemd, a system and service manager for Linux, compatible with the SysV and LSB init scripts. It provides aggressive parallelism capabilities, uses socket and D-Bus activation for starting services, offers on-demand starting of daemons, and keeps track of processes using Linux cgroups.

*Credits: N/A

CVSS Scores

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Attack Vector

Local

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

Low

Availability

High

Attack Vector

Local

Attack Complexity

Low

Authentication

None

Confidentiality

None

Integrity

None

Availability

Complete

Attack Vector

Local

Attack Complexity

Low

Authentication

None

Confidentiality

None

Integrity

Partial

Availability

Complete

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2016-09-09 CVE Reserved
2016-10-13 CVE Published
2024-08-06 CVE Updated
2024-08-06 First Exploit
2025-03-30 EPSS Updated
---------- Exploited in Wild
---------- KEV Due Date

CWE

CWE-20: Improper Input Validation
CWE-617: Reachable Assertion

CAPEC

References (11)

URL	Tag	Source
http://www.openwall.com/lists/oss-security/2016/09/28/9	Mailing List
http://www.openwall.com/lists/oss-security/2016/09/30/1	Mailing List
http://www.securityfocus.com/bid/93223	Third Party Advisory
http://www.securitytracker.com/id/1037320	Vdb Entry

URL	Date	SRC
https://github.com/systemd/systemd/issues/4234	2024-08-06
https://www.agwa.name/blog/post/how_to_crash_systemd_in_one_tweet	2024-08-06

URL	Date	SRC

URL	Date	SRC
http://rhn.redhat.com/errata/RHSA-2016-2610.html	2017-07-28
http://rhn.redhat.com/errata/RHSA-2016-2694.html	2017-07-28
http://www.ubuntu.com/usn/USN-3094-1	2017-07-28
https://access.redhat.com/security/cve/CVE-2016-7795	2016-11-09
https://bugzilla.redhat.com/show_bug.cgi?id=1380286	2016-11-09

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Canonical Search vendor "Canonical"		Ubuntu Linux Search vendor "Canonical" for product "Ubuntu Linux"				16.04 Search vendor "Canonical" for product "Ubuntu Linux" and version "16.04"		lts		Affected
Systemd Project Search vendor "Systemd Project"		Systemd Search vendor "Systemd Project" for product "Systemd"				<= 231 Search vendor "Systemd Project" for product "Systemd" and version " <= 231"		-		Affected