SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2021-33971

Qihoo 360 (https://www.360.cn/) Qihoo 360 Safeguard (https://www.360.cn/) Qihoo 360 Total Security (http://www.360totalsecurity.com/) is affected by: Buffer Overflow.

HIGH 7.8EPSS 0.42%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.42%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

Qihoo 360 (https://www.360.cn/) Qihoo 360 Safeguard (https://www.360.cn/) Qihoo 360 Total Security (http://www.360totalsecurity.com/) is affected by: Buffer Overflow. The impact is: execute arbitrary code (local). The component is: This is a set of vulnerabilities affecting popular software, "360 Safeguard(12.1.0.1004,12.1.0.1005,13.1.0.1001)" , "360 Total Security(10.8.0.1060,10.8.0.1213)", "360 Safe Browser & 360 Chrome(13.0.2170.0)". The attack vector is: On the browser vulnerability, just open a link to complete the vulnerability exploitation remotely; on the client software, you need to locally execute the vulnerability exploitation program, which of course can be achieved with the full chain of browser vulnerability. ¶¶ This is a set of the most serious vulnerabilities that exist on Qihoo 360's PC client a variety of popular software, remote vulnerabilities can be completed by opening a link to arbitrary code execution on both security browsers, with the use of local vulnerabilities, not only help the vulnerability code constitutes an escalation of privileges, er can make the spyware persistent without being scanned permanently resides on the target PC computer (because local vulnerability against Qihoo 360 company's antivirus kernel flaws); this group of remote and local vulnerability of the perfect match, to achieve an information security fallacy, in Qihoo 360's antivirus vulnerability, not only can not be scanned out of the virus, but will help the virus persistently control the target computer, while Qihoo 360 claims to be a safe browser, which exists in the kernel vulnerability but helped the composition of the remote vulnerability. (Security expert "Memory Corruptor" have reported this set of vulnerabilities to the corresponding vendor, all vulnerabilities have been fixed and the vendor rewarded thousands of dollars to the security experts)

CVSS 3.1
7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS
0.42% probability · 36th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-120
Affected
360/total security
Source
cve@mitre.org
EPSS trend
0%3%5%26 October 2026: 0.42%26 October 202626 October 2026

EPSS 0.4% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.