CVE-2021-45604 [Medium] | Out-of-bounds Write in Cbr750 Firmware

Certain NETGEAR devices are affected by a stack-based buffer overflow by an authenticated user. This affects CBR750 before 3.2.18.2, D6220 before 1.0.0.68, D6400 before 1.0.0.102, D8500 before 1.0.3.60, LAX20 before 1.1.6.28, MK62 before 1.0.6.116, MR60 before 1.0.6.116, MS60 before 1.0.6.116, R6300v2 before 1.0.4.50, R6400 before 1.0.1.68, R6400v2 before 1.0.4.118, R6700v3 before 1.0.4.118, R6900P before 1.3.3.140, R7000 before 1.0.11.116, R7000P before 1.3.3.140, R7850 before 1.0.5.68, R7900 before 1.0.4.38, R7900P before 1.4.2.84, R7960P before 1.4.2.84, R8000 before 1.0.4.68, R8000P before 1.4.2.84, RAX15 before 1.0.3.96, RAX20 before 1.0.3.96, RAX200 before 1.0.4.120, RAX35v2 before 1.0.3.96, RAX40v2 before 1.0.3.96, RAX43 before 1.0.3.96, RAX45 before 1.0.3.96, RAX50 before 1.0.3.96, RAX75 before 1.0.4.120, RAX80 before 1.0.4.120, RBK752 before 3.2.17.12, RBK852 before 3.2.17.12, RBR750 before 3.2.17.12, RBR850 before 3.2.17.12, RBS750 before 3.2.17.12, RBS850 before 3.2.17.12, RS400 before 1.5.1.80, and XR1000 before 1.0.0.58.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-06-15	0.08%	0.37%	+0.29%
2	2025-03-17	0.04%	0.08%	+0.04%
3	2023-03-07	—	0.04%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-06-15

0.08%

0.37%

+0.29%

2025-03-17

0.04%

0.08%

+0.04%

2023-03-07

—

0.04%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
4.5	3.1	MEDIUM	`CVSS:3.1/AV:A/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H` Click to expand Attack vector (AV:A) Attacker has to be nearby on the network—same office, same link, that vibe—not the whole wide internet. 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:H) They need powerful rights—admin, root, or similar—before this pays off. 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:N) Data isn’t meaningfully altered or forged. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.	0.9	3.6	[email protected]
4.5	3.1	MEDIUM	`CVSS:3.1/AV:A/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H` Click to expand Attack vector (AV:A) Attacker has to be nearby on the network—same office, same link, that vibe—not the whole wide internet. 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:H) They need powerful rights—admin, root, or similar—before this pays off. 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:N) Data isn’t meaningfully altered or forged. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.	0.9	3.6	[email protected]
2.7	2.0	LOW	`AV:A/AC:L/Au:S/C:N/I:N/A:P` Click to expand Access vector (AV:A) Requires access to an adjacent network segment. Access complexity (AC:L) Exploitation conditions are straightforward and predictable. Authentication (AU:S) A single authentication is required. Confidentiality impact (C:N) No confidentiality impact. Integrity impact (I:N) No integrity impact. Availability impact (A:P) Partial availability impact.	5.1	2.9	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

4.5

3.1

MEDIUM

CVSS:3.1/AV:A/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H Click to expand

Attack vector (AV:A): Attacker has to be nearby on the network—same office, same link, that vibe—not the whole wide internet.
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:H): They need powerful rights—admin, root, or similar—before this pays off.
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:N): Data isn’t meaningfully altered or forged.
Availability (A:H): Could take the service down hard or make it unusable for people who depend on it.

0.9

3.6

[email protected]

4.5

3.1

MEDIUM

CVSS:3.1/AV:A/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H Click to expand

Attack vector (AV:A): Attacker has to be nearby on the network—same office, same link, that vibe—not the whole wide internet.
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:H): They need powerful rights—admin, root, or similar—before this pays off.
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:N): Data isn’t meaningfully altered or forged.
Availability (A:H): Could take the service down hard or make it unusable for people who depend on it.

0.9

3.6

[email protected]

2.7

2.0

LOW

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

Access vector (AV:A): Requires access to an adjacent network segment.
Access complexity (AC:L): Exploitation conditions are straightforward and predictable.
Authentication (AU:S): A single authentication is required.
Confidentiality impact (C:N): No confidentiality impact.
Integrity impact (I:N): No integrity impact.
Availability impact (A:P): Partial availability impact.

5.1

2.9

[email protected]

Affected software / configurations for CVE-2021-45604

Vendor	Product	Version	Raw CPE
netgear	cbr750_firmware	< 3.2.18.2	cpe:2.3:o:netgear:cbr750_firmware::::::::
netgear	d6220_firmware	< 1.0.0.68	cpe:2.3:o:netgear:d6220_firmware::::::::
netgear	d6400_firmware	< 1.0.0.102	cpe:2.3:o:netgear:d6400_firmware::::::::
netgear	d8500_firmware	< 1.0.3.60	cpe:2.3:o:netgear:d8500_firmware::::::::
netgear	lax20_firmware	< 1.1.6.28	cpe:2.3:o:netgear:lax20_firmware::::::::
netgear	mk62_firmware	< 1.0.6.116	cpe:2.3:o:netgear:mk62_firmware::::::::
netgear	mr60_firmware	< 1.0.6.116	cpe:2.3:o:netgear:mr60_firmware::::::::
netgear	ms60_firmware	< 1.0.6.116	cpe:2.3:o:netgear:ms60_firmware::::::::
netgear	r6300_firmware	< 1.0.4.50	cpe:2.3:o:netgear:r6300_firmware::::::::
netgear	r6400_firmware	< 1.0.1.68	cpe:2.3:o:netgear:r6400_firmware::::::::
netgear	r6400_firmware	< 1.0.4.118	cpe:2.3:o:netgear:r6400_firmware::::::::
netgear	r6700_firmware	< 1.0.4.118	cpe:2.3:o:netgear:r6700_firmware::::::::
netgear	r6900p_firmware	< 1.3.3.140	cpe:2.3:o:netgear:r6900p_firmware::::::::
netgear	r7000_firmware	< 1.0.11.116	cpe:2.3:o:netgear:r7000_firmware::::::::
netgear	r7000p_firmware	< 1.3.3.140	cpe:2.3:o:netgear:r7000p_firmware::::::::
netgear	r7850_firmware	< 1.0.5.68	cpe:2.3:o:netgear:r7850_firmware::::::::
netgear	r7900_firmware	< 1.0.4.38	cpe:2.3:o:netgear:r7900_firmware::::::::
netgear	r7900p_firmware	< 1.4.2.84	cpe:2.3:o:netgear:r7900p_firmware::::::::
netgear	r7960p_firmware	< 1.4.2.84	cpe:2.3:o:netgear:r7960p_firmware::::::::
netgear	r8000_firmware	< 1.0.4.68	cpe:2.3:o:netgear:r8000_firmware::::::::
netgear	r8000p_firmware	< 1.4.2.84	cpe:2.3:o:netgear:r8000p_firmware::::::::
netgear	rax15_firmware	< 1.0.3.96	cpe:2.3:o:netgear:rax15_firmware::::::::
netgear	rax20_firmware	< 1.0.3.96	cpe:2.3:o:netgear:rax20_firmware::::::::
netgear	rax200_firmware	< 1.0.4.120	cpe:2.3:o:netgear:rax200_firmware::::::::
netgear	rax35_firmware	< 1.0.3.96	cpe:2.3:o:netgear:rax35_firmware::::::::
netgear	rax40_firmware	< 1.0.3.96	cpe:2.3:o:netgear:rax40_firmware::::::::
netgear	rax43_firmware	< 1.0.3.96	cpe:2.3:o:netgear:rax43_firmware::::::::
netgear	rax45_firmware	< 1.0.3.96	cpe:2.3:o:netgear:rax45_firmware::::::::
netgear	rax50_firmware	< 1.0.3.96	cpe:2.3:o:netgear:rax50_firmware::::::::
netgear	rax75_firmware	< 1.0.4.120	cpe:2.3:o:netgear:rax75_firmware::::::::
netgear	rax80_firmware	< 1.0.4.120	cpe:2.3:o:netgear:rax80_firmware::::::::
netgear	rbk752_firmware	< 3.2.17.12	cpe:2.3:o:netgear:rbk752_firmware::::::::
netgear	rbk852_firmware	< 3.2.17.12	cpe:2.3:o:netgear:rbk852_firmware::::::::
netgear	rbr750_firmware	< 3.2.17.12	cpe:2.3:o:netgear:rbr750_firmware::::::::
netgear	rbr850_firmware	< 3.2.17.12	cpe:2.3:o:netgear:rbr850_firmware::::::::
netgear	rbs750_firmware	< 3.2.17.12	cpe:2.3:o:netgear:rbs750_firmware::::::::
netgear	rbs850_firmware	< 3.2.17.12	cpe:2.3:o:netgear:rbs850_firmware::::::::
netgear	rs400_firmware	< 1.5.1.80	cpe:2.3:o:netgear:rs400_firmware::::::::
netgear	xr1000_firmware	< 1.0.0.58	cpe:2.3:o:netgear:xr1000_firmware::::::::

References for CVE-2021-45604

URL	Tags
https://kb.netgear.com/000064526/Security-Advisory-for-Post-Authentication-Stack-Overflow-on-Some-Routers-and-WiFi-Systems-PSV-2020-0572	Patch Vendor Advisory

URL

CVE-2021-45604

Exploit prediction scoring system (EPSS) score for CVE-2021-45604

Common vulnerability scoring system (CVSS) metrics for CVE-2021-45604

Weakness enumeration for CVE-2021-45604

Affected software / configurations for CVE-2021-45604

References for CVE-2021-45604