CVE Vulnerabilities

CVE-2019-9717

Uncontrolled Resource Consumption

Published: Sep 19, 2019 | Modified: Jul 21, 2021
CVSS 3.x
6.5
MEDIUM
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
CVSS 2.x
7.1 HIGH
AV:N/AC:M/Au:N/C:N/I:N/A:C
RedHat/V2
RedHat/V3
Ubuntu
MEDIUM

In Libav 12.3, a denial of service in the subtitle decoder allows attackers to hog the CPU via a crafted video file in Matroska format, because srt_to_ass in libavcodec/srtdec.c has a complex format argument to sscanf.

Weakness

The product does not properly control the allocation and maintenance of a limited resource, thereby enabling an actor to influence the amount of resources consumed, eventually leading to the exhaustion of available resources.

Affected Software

Name Vendor Start Version End Version
Libav Libav * 12.3 (including)
Ffmpeg Ubuntu trusty *
Gst-libav1.0 Ubuntu bionic *
Gst-libav1.0 Ubuntu disco *
Gst-libav1.0 Ubuntu eoan *
Gst-libav1.0 Ubuntu groovy *
Gst-libav1.0 Ubuntu hirsute *
Gst-libav1.0 Ubuntu impish *
Gst-libav1.0 Ubuntu kinetic *
Gst-libav1.0 Ubuntu lunar *
Gst-libav1.0 Ubuntu mantic *
Gst-libav1.0 Ubuntu trusty *
Gst-libav1.0 Ubuntu xenial *
Qtwebengine-opensource-src Ubuntu bionic *
Qtwebengine-opensource-src Ubuntu disco *
Qtwebengine-opensource-src Ubuntu eoan *
Qtwebengine-opensource-src Ubuntu groovy *
Qtwebengine-opensource-src Ubuntu hirsute *
Qtwebengine-opensource-src Ubuntu impish *
Qtwebengine-opensource-src Ubuntu kinetic *
Qtwebengine-opensource-src Ubuntu lunar *
Qtwebengine-opensource-src Ubuntu mantic *
Qtwebengine-opensource-src Ubuntu trusty *
Vice Ubuntu bionic *
Vice Ubuntu disco *
Vice Ubuntu eoan *
Vice Ubuntu groovy *
Vice Ubuntu hirsute *
Vice Ubuntu impish *
Vice Ubuntu kinetic *
Vice Ubuntu lunar *
Vice Ubuntu mantic *
Vice Ubuntu trusty *
Vice Ubuntu xenial *

Extended Description

Limited resources include memory, file system storage, database connection pool entries, and CPU. If an attacker can trigger the allocation of these limited resources, but the number or size of the resources is not controlled, then the attacker could cause a denial of service that consumes all available resources. This would prevent valid users from accessing the product, and it could potentially have an impact on the surrounding environment. For example, a memory exhaustion attack against an application could slow down the application as well as its host operating system. There are at least three distinct scenarios which can commonly lead to resource exhaustion:

Resource exhaustion problems are often result due to an incorrect implementation of the following situations:

Potential Mitigations

  • Mitigation of resource exhaustion attacks requires that the target system either:

  • The first of these solutions is an issue in itself though, since it may allow attackers to prevent the use of the system by a particular valid user. If the attacker impersonates the valid user, they may be able to prevent the user from accessing the server in question.

  • The second solution is simply difficult to effectively institute – and even when properly done, it does not provide a full solution. It simply makes the attack require more resources on the part of the attacker.

References