CVE-2019-9816

MEDIUM

Thunderbird <60.7-Firefox <67-Firefox ESR <60.7 - Code Injection

Title source: llm

Exploitation Summary

EIP tracks 1 public exploit for CVE-2019-9816. PoCs published by Google Security Research.

AI-analyzed exploit summary This JavaScript PoC exploits a type confusion vulnerability in Mozilla's SpiderMonkey engine by manipulating ObjectGroup assumptions during JIT compilation, leading to a crash in debug builds and potential arbitrary code execution in release builds.

Description

A possible vulnerability exists where type confusion can occur when manipulating JavaScript objects in object groups, allowing for the bypassing of security checks within these groups. *Note: this vulnerability has only been demonstrated with UnboxedObjects, which are disabled by default on all supported releases.*. This vulnerability affects Thunderbird < 60.7, Firefox < 67, and Firefox ESR < 60.7.

Exploits (1)

exploitdb WORKING POC VERIFIED

by Google Security Research · textdosmultiple

https://www.exploit-db.com/exploits/46940

View Code ZIP pw:eip

This JavaScript PoC exploits a type confusion vulnerability in Mozilla's SpiderMonkey engine by manipulating ObjectGroup assumptions during JIT compilation, leading to a crash in debug builds and potential arbitrary code execution in release builds.

Classification

Working Poc 95%

Attack Type

Rce

Complexity

Complex

Reliability

Reliable

Target: Mozilla SpiderMonkey (Firefox JavaScript engine)

No auth needed

Prerequisites: Target must be running a vulnerable version of SpiderMonkey with UnboxedObjects enabled

MITRE ATT&CK

T1190 - Exploit Public-Facing Application

devstral-2 · analyzed Feb 16, 2026 Full analysis →

References (4)

Core 4

Core References

Vendor Advisory x_refsource_misc

https://www.mozilla.org/security/advisories/mfsa2019-13/

Vendor Advisory x_refsource_misc

https://www.mozilla.org/security/advisories/mfsa2019-15/

Vendor Advisory x_refsource_misc

https://www.mozilla.org/security/advisories/mfsa2019-14/

Permissions Required x_refsource_misc

https://bugzilla.mozilla.org/show_bug.cgi?id=1536768

Scores

CVSS v3 5.9

EPSS 0.0617

EPSS Percentile 92.6%

Attack Vector NETWORK

CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N

Details

CWE

CWE-843

Status published

Products (3)

mozilla/firefox < 67.0

mozilla/firefox_esr < 60.7

mozilla/thunderbird < 60.7

Published Jul 23, 2019

Tracked Since Feb 18, 2026