CVE-2021-4198 [Medium] | Security Vulnerability in Antivirus Plus

A NULL Pointer Dereference vulnerability in the messaging_ipc.dll component as used in Bitdefender Total Security, Internet Security, Antivirus Plus, Endpoint Security Tools, VPN Standalone allows an attacker to arbitrarily crash product processes and generate crashdump files. This issue affects: Bitdefender Total Security versions prior to 26.0.3.29. Bitdefender Internet Security versions prior to 26.0.3.29. Bitdefender Antivirus Plus versions prior to 26.0.3.29. Bitdefender Endpoint Security Tools versions prior to 7.2.2.92. Bitdefender VPN Standalone versions prior to 25.5.0.48.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2025-03-30	0.17%	0.06%	-0.12%
2	2025-03-29	0.06%	0.17%	+0.12%
3	2025-03-25	—	0.06%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2025-03-30

0.17%

0.06%

-0.12%

2025-03-29

0.06%

0.17%

+0.12%

2025-03-25

—

0.06%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
6.1	3.1	MEDIUM	`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/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:N) Doesn’t really leak secrets in a meaningful way. Integrity (I:L) Attackers could change some data, but it’s limited—not everything goes. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.	1.8	4.2	[email protected]
6.1	3.1	MEDIUM	`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/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:N) Doesn’t really leak secrets in a meaningful way. Integrity (I:L) Attackers could change some data, but it’s limited—not everything goes. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.	1.8	4.2	[email protected]
3.6	2.0	LOW	`AV:L/AC:L/Au:N/C:N/I:P/A:P` Click to expand Access vector (AV:L) Requires local access to the target system. Access complexity (AC:L) Exploitation conditions are straightforward and predictable. Authentication (AU:N) No authentication is required. Confidentiality impact (C:N) No confidentiality impact. Integrity impact (I:P) Partial integrity impact. Availability impact (A:P) Partial availability impact.	3.9	4.9	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

6.1

3.1

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/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:N): Doesn’t really leak secrets in a meaningful way.
Integrity (I:L): Attackers could change some data, but it’s limited—not everything goes.
Availability (A:H): Could take the service down hard or make it unusable for people who depend on it.

1.8

4.2

[email protected]

6.1

3.1

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/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:N): Doesn’t really leak secrets in a meaningful way.
Integrity (I:L): Attackers could change some data, but it’s limited—not everything goes.
Availability (A:H): Could take the service down hard or make it unusable for people who depend on it.

1.8

4.2

[email protected]

3.6

2.0

LOW

AV:L/AC:L/Au:N/C:N/I:P/A:P Click to expand

Access vector (AV:L): Requires local access to the target system.
Access complexity (AC:L): Exploitation conditions are straightforward and predictable.
Authentication (AU:N): No authentication is required.
Confidentiality impact (C:N): No confidentiality impact.
Integrity impact (I:P): Partial integrity impact.
Availability impact (A:P): Partial availability impact.

3.9

4.9

[email protected]

Affected software / configurations for CVE-2021-4198

Vendor	Product	Version	Raw CPE
bitdefender	antivirus_plus	< 26.0.3.29	cpe:2.3:a:bitdefender:antivirus_plus::::::::
bitdefender	endpoint_security_tools	< 7.2.2.92	cpe:2.3:a:bitdefender:endpoint_security_tools::::::::
bitdefender	internet_security	< 26.0.3.29	cpe:2.3:a:bitdefender:internet_security::::::::
bitdefender	total_security	< 26.0.3.29	cpe:2.3:a:bitdefender:total_security::::::::
bitdefender	vpn_standalone	< 25.5.0.48	cpe:2.3:a:bitdefender:vpn_standalone::::::::

References for CVE-2021-4198

URL	Tags
https://www.bitdefender.com/support/security-advisories/messaging_ipc-dll-null-pointer-dereference-in-multiple-bitdefender-products-va-10016/	Vendor Advisory
https://www.zerodayinitiative.com/advisories/ZDI-22-483/	Third Party Advisory

URL

CVE-2021-4198 | messaging_ipc.dll NULL Pointer Dereference in multiple Bitdefender products (VA-10016)

Exploit prediction scoring system (EPSS) score for CVE-2021-4198

Common vulnerability scoring system (CVSS) metrics for CVE-2021-4198

Weakness enumeration for CVE-2021-4198

Affected software / configurations for CVE-2021-4198

References for CVE-2021-4198