CVE-2019-11759
Mozilla: Stack buffer overflow in HKDF output
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · October 22, 2019
Updated · November 22, 2025
Description
A flaw was discovered in both Firefox and Thunderbird where 4 bytes of a HMAC output could be written past the end of a buffer stored on the memory stack. This could allow an attacker to execute arbitrary code or lead to a crash. This flaw can be exploited over the network.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
No mitigation is specified in collected source.
CVSS / CWE
CVSS 3.1 · 8.8CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CWE-120 · Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')