CVE-2021-33971

Exp

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)

Published: 2023-04-19 Last update: 2025-02-05 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2021-33971 is rated Exploit Available (59.9/100): CVSS High severity, with low exploitation likelihood (EPSS 0.17%). Core evidence: 2 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2021-33971

EDB-ID Source Kind Published Link
nvd_ref exploit_tag Exploit-DB ↗
nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2021-33971

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-04-21 0.05% 0.17% +0.12%
2 2026-02-13 0.04% 0.05% +0.01%
3 2026-01-22 0.04%

Full EPSS history (8 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-33971

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.8 3.1 HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
1.8 5.9 [email protected]
7.8 3.1 HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
1.8 5.9 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2021-33971

Affected software / configurations for CVE-2021-33971

Vendor Product Version Raw CPE
360 total_security 10.8.0.1060 cpe:2.3:a:360:total_security:10.8.0.1060:*:*:*:*:*:*:*

References for CVE-2021-33971

cvelogic Threat Intelligence