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.

References

• https://nvd.nist.gov/vuln/detail/CVE-2019-17021
• 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