CVE-2019-11759

An attacker could have caused 4 bytes of HMAC output to be written past the end of a buffer stored on the stack. This could be used by an attacker to execute arbitrary code or more likely lead to a crash. This vulnerability affects Firefox < 70, Thunderbird < 68.2, and Firefox ESR < 68.2.

• CWE-120

• https://bugzilla.mozilla.org/show_bug.cgi?id=1577953Issue Tracking, Permissions Required
• https://security.gentoo.org/glsa/202003-10Third Party Advisory
• https://usn.ubuntu.com/4335-1/Third Party Advisory
• https://www.mozilla.org/security/advisories/mfsa2019-33/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2019-34/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2019-35/Vendor Advisory
• https://bugzilla.mozilla.org/show_bug.cgi?id=1577953Issue Tracking, Permissions Required
• https://security.gentoo.org/glsa/202003-10Third Party Advisory
• https://usn.ubuntu.com/4335-1/Third Party Advisory
• https://www.mozilla.org/security/advisories/mfsa2019-33/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2019-34/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2019-35/Vendor Advisory

Published

Jan 8, 2020

Last Modified

Jun 17, 2026

Status

Modified

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
• Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
• PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
• AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.

• CVE-2019-11753The Firefox installer allows Firefox to be installed to a cu…7.8
• CVE-2019-11754When the pointer lock is enabled by a website though request…4.3
• CVE-2019-11755A crafted S/MIME message consisting of an inner encryption l…7.5
• CVE-2019-11756Improper refcounting of soft token session objects could cau…8.8
• CVE-2019-11757When following the value's prototype chain, it was possible …8.8
• CVE-2019-11758Mozilla community member Philipp reported a memory safety bu…8.8
• CVE-2019-1176An elevation of privilege vulnerability exists when DirectX …7
• CVE-2019-11760A fixed-size stack buffer could overflow in nrappkit when do…8.8
• CVE-2019-11761By using a form with a data URI it was possible to gain acce…5.4
• CVE-2019-11762If two same-origin documents set document.domain differently…6.1
• CVE-2019-11763Failure to correctly handle null bytes when processing HTML …6.1
• CVE-2019-11764Mozilla developers and community members reported memory saf…8.8