Exploit: Belmoo Trojan.
Vulnerable component: Mozilla Firefox
CVSSv3 score: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H/E:H/RL:O/RC:C
CWE-ID: CWE-119 - Improper Restriction of Operations within the Bounds of a Memory Buffer
The vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to boundary error within nsCSSFrameConstructor::ContentAppended. A remote attacker can create a specially crafted web page containing specially crafted document.write and appendChild calls, cause heap-based buffer overflow and execute arbitrary code on the target system with privileges of the current user.
Successful exploitation of this vulnerability may allow an attacker to compromise vulnerable system.
Note: this vulnerability is being actively exploited.
Known APT campaigns:
Nobel Peace Prize ceremony beach
The group behind this attack was also behind Sunshop.The attack server located in Taiwan spread malicious HTML file as Trojan.Malscript and the downloaded threat as Backdoor.Belmoo.
- Mozilla Firefox - Memory Corruption PoC (Simplified) [Exploit-DB]