CVE-2019-17021

Severity: medium (CVSS 5.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.9% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2020-01-08 · updated 2026-06-17
Weakness: CWE-362

Description

During the initialization of a new content process, a race condition occurs that can allow a content process to disclose heap addresses from the parent process. *Note: this issue only occurs on Windows. Other operating systems are unaffected.*. This vulnerability affects Firefox ESR < 68.4 and Firefox < 72.

Affected products

Mozilla Firefox: before 72.0 — fixed in 72.0
Mozilla Firefox ESR: before 68.4 — fixed in 68.4
openSUSE Leap: 15.1

How to fix

Upgrade to a fixed version: Mozilla Firefox 72.0; Mozilla Firefox ESR 68.4. Check the vendor advisory for mitigations.

References

http://lists.opensuse.org/opensuse-security-announce/2020-01/msg00029.html
http://lists.opensuse.org/opensuse-security-announce/2020-01/msg00043.html
http://packetstormsecurity.com/files/155912/Slackware-Security-Advisory-mozilla-thunderbird-Updates.html
https://bugzilla.mozilla.org/show_bug.cgi?id=1599008
https://seclists.org/bugtraq/2020/Jan/18
https://www.mozilla.org/security/advisories/mfsa2020-01/
https://www.mozilla.org/security/advisories/mfsa2020-02/
http://lists.opensuse.org/opensuse-security-announce/2020-01/msg00029.html
http://lists.opensuse.org/opensuse-security-announce/2020-01/msg00043.html
http://packetstormsecurity.com/files/155912/Slackware-Security-Advisory-mozilla-thunderbird-Updates.html
https://bugzilla.mozilla.org/show_bug.cgi?id=1599008
https://seclists.org/bugtraq/2020/Jan/18

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