CVE-2019-11756: Use After Free

Published Nov 21, 2019
·
Updated

A use-after-free flaw was found in Mozilla Network Security Services (NSS) related to PK11 session handling. An attacker could use this flaw to execute arbitrary code with the permissions of the user running the application compiled with NSS.

Other sources

A use-after-free was found in Mozilla nss, related to PK11 session handling. An attacker could this to execute arbitrary code with the permissions of user running the application (compiled with nss). This flaw is difficult to trigger (even impossible as per upstream)

Red Hat

Improper refcounting of soft token session objects could cause a use-after-free and crash (likely limited to a denial of service).

Mozilla Firefox could allow a remote attacker to execute arbitrary code on the system, caused by a use-after-free of SFTKSession object. By persuading a victim to visit a specially-crafted Web site, a remote attacker could exploit this vulnerability using unknown attack vectors to execute arbitrary code on the vulnerable system or cause a denial of service.

IBM

Affected Software

21 affected componentsFixes available
redhat/nspr<0:4.25.0-2.el7_9
0:4.25.0-2.el7_9
redhat/nss<0:3.53.1-3.el7_9
0:3.53.1-3.el7_9
redhat/nss-softokn<0:3.53.1-6.el7_9
0:3.53.1-6.el7_9
redhat/nss-util<0:3.53.1-1.el7_9
0:3.53.1-1.el7_9
redhat/nss-softokn<0:3.28.3-10.el7_4
0:3.28.3-10.el7_4
redhat/nss<0:3.36.0-9.el7_6
0:3.36.0-9.el7_6
redhat/nss-softokn<0:3.36.0-7.el7_6
0:3.36.0-7.el7_6
redhat/nss-softokn<0:3.44.0-9.el7_7
0:3.44.0-9.el7_7
redhat/nspr<0:4.25.0-2.el8_2
0:4.25.0-2.el8_2
redhat/nss<0:3.53.1-11.el8_2
0:3.53.1-11.el8_2
redhat/nss<3.47
3.47
Mozilla Firefox<71
71
Mozilla Firefox<71.0
debian/firefox
137.0.1-1
IBM Security Guardium<=10.5
IBM Security Guardium<=10.6
IBM Security Guardium<=11.0
IBM Security Guardium<=11.1
IBM Security Guardium<=11.2
IBM Security Guardium<=11.3
IBM Security Guardium<=11.4

Event History

Dec 3, 2019
CVE Published
12:00 AM
Jan 8, 2020
CVE Published
via MITRE·07:23 PM
Data Sourced
via MITRE·07:23 PM
DescriptionWeakness
Jan 11, 2024
Data Sourced
via Launchpad·11:14 PM
Description
Sep 16, 2024
Data Sourced
via Ubuntu·02:09 AM
RemedyDescriptionSeverityAffected Software
Apr 12, 2025
Data Sourced
via Debian·04:04 AM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is CVE-2019-11756?

CVE-2019-11756 is a vulnerability in Mozilla Firefox that could allow a remote attacker to execute arbitrary code on the system.

2

What is the severity of CVE-2019-11756?

The severity of CVE-2019-11756 is high, with a CVSS score of 8.8.

3

How does CVE-2019-11756 occur?

CVE-2019-11756 occurs due to improper refcounting of soft token session objects, leading to a use-after-free vulnerability.

4

How can an attacker exploit CVE-2019-11756?

An attacker can exploit CVE-2019-11756 by persuading a victim to visit a specially-crafted website.

5

How can I protect myself from CVE-2019-11756?

To protect yourself from CVE-2019-11756, ensure that you have applied the necessary security updates provided by Mozilla Firefox or your operating system vendor.

Contact

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