CVE Vulnerabilities

CVE-2019-15892

Reachable Assertion

Published: Sep 03, 2019 | Modified: Jun 21, 2022
CVSS 3.x
7.5
HIGH
Source:
NVD
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS 2.x
7.8 HIGH
AV:N/AC:L/Au:N/C:N/I:N/A:C
RedHat/V2
RedHat/V3
7.5 MODERATE
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Ubuntu

An issue was discovered in Varnish Cache before 6.0.4 LTS, and 6.1.x and 6.2.x before 6.2.1. An HTTP/1 parsing failure allows a remote attacker to trigger an assert by sending crafted HTTP/1 requests. The assert will cause an automatic restart with a clean cache, which makes it a Denial of Service attack.

Weakness

The product contains an assert() or similar statement that can be triggered by an attacker, which leads to an application exit or other behavior that is more severe than necessary.

Affected Software

Name Vendor Start Version End Version
Varnish Varnish-cache 6.0.0 *
Varnish_cache Varnish-cache 6.2.0 *
Varnish_cache Varnish-cache 6.1.0 6.1.1
Red Hat Enterprise Linux 8 RedHat varnish:6-8030020200530080205.30b713e6 *
Red Hat Software Collections for Red Hat Enterprise Linux 7 RedHat rh-varnish6-0:4.1-6.el7 *
Red Hat Software Collections for Red Hat Enterprise Linux 7 RedHat rh-varnish6-varnish-0:6.0.6-1.el7 *
Red Hat Software Collections for Red Hat Enterprise Linux 7 RedHat rh-varnish6-varnish-modules-0:0.15.0-6.el7 *
Red Hat Software Collections for Red Hat Enterprise Linux 7.6 EUS RedHat rh-varnish6-0:4.1-6.el7 *
Red Hat Software Collections for Red Hat Enterprise Linux 7.6 EUS RedHat rh-varnish6-varnish-0:6.0.6-1.el7 *
Red Hat Software Collections for Red Hat Enterprise Linux 7.6 EUS RedHat rh-varnish6-varnish-modules-0:0.15.0-6.el7 *
Red Hat Software Collections for Red Hat Enterprise Linux 7.7 EUS RedHat rh-varnish6-0:4.1-6.el7 *
Red Hat Software Collections for Red Hat Enterprise Linux 7.7 EUS RedHat rh-varnish6-varnish-0:6.0.6-1.el7 *
Red Hat Software Collections for Red Hat Enterprise Linux 7.7 EUS RedHat rh-varnish6-varnish-modules-0:0.15.0-6.el7 *
Varnish Ubuntu disco *
Varnish Ubuntu eoan *
Varnish Ubuntu trusty *
Varnish Ubuntu upstream *

Extended Description

While assertion is good for catching logic errors and reducing the chances of reaching more serious vulnerability conditions, it can still lead to a denial of service. For example, if a server handles multiple simultaneous connections, and an assert() occurs in one single connection that causes all other connections to be dropped, this is a reachable assertion that leads to a denial of service.

Potential Mitigations

References