CVE-2021-33684 [Medium] | Out-of-bounds Write in Netweaver Abap

SAP NetWeaver AS ABAP and ABAP Platform, versions - KRNL32NUC 7.21, 7.21EXT, 7.22, 7.22EXT, KRNL32UC 7.21, 7.21EXT, 7.22, 7.22EXT, KRNL64NUC 7.21, 7.21EXT, 7.22, 7.22EXT, 7.49, KRNL64UC 8.04, 7.21, 7.21EXT, 7.22, 7.22EXT, 7.49, 7.53, KERNEL 8.04, 7.21, 7.21EXT, 7.22, 7.22EXT, 7.49, 7.53, 7.77, 7.81, 7.84, allows an attacker to send overlong content in the RFC request type thereby crashing the corresponding work process because of memory corruption vulnerability. The work process will attempt to restart itself after the crash and hence the impact on the availability is low.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2025-11-21	0.27%	0.18%	-0.09%
2	2025-11-18	0.18%	0.27%	+0.09%
3	2025-03-30	—	0.18%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2025-11-21

0.27%

0.18%

-0.09%

2025-11-18

0.18%

0.27%

+0.09%

2025-03-30

—

0.18%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
5.3	3.1	MEDIUM	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L` Click to expand Attack vector (AV:N) Could be attacked over the internet or any normal routed network—not just someone sitting at the machine. 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:N) No account or special rights needed—anonymous or random user is enough. 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:L) Might cause slowdowns, glitches, or partial disruption—not a full brick.	3.9	1.4	[email protected]
5.3	3.0	MEDIUM	`CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L` Click to expand Attack vector (AV:N) Could be attacked over the internet or any normal routed network—not just someone sitting at the machine. 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:N) No account or special rights needed—anonymous or random user is enough. 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:L) Might cause slowdowns, glitches, or partial disruption—not a full brick.	3.9	1.4	[email protected]
5.0	2.0	MEDIUM	`AV:N/AC:L/Au:N/C:N/I:N/A:P` Click to expand Access vector (AV:N) Can be exploited remotely over network reachability. 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:N) No integrity impact. Availability impact (A:P) Partial availability impact.	10.0	2.9	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

5.3

3.1

MEDIUM

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

Attack vector (AV:N): Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
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:N): No account or special rights needed—anonymous or random user is enough.
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:L): Might cause slowdowns, glitches, or partial disruption—not a full brick.

3.9

1.4

[email protected]

5.3

3.0

MEDIUM

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L Click to expand

Attack vector (AV:N): Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
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:N): No account or special rights needed—anonymous or random user is enough.
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:L): Might cause slowdowns, glitches, or partial disruption—not a full brick.

3.9

1.4

[email protected]

5.0

2.0

MEDIUM

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

Access vector (AV:N): Can be exploited remotely over network reachability.
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:N): No integrity impact.
Availability impact (A:P): Partial availability impact.

10.0

2.9

[email protected]

Affected software / configurations for CVE-2021-33684

Vendor	Product	Version	Raw CPE
sap	netweaver_abap	7.21	cpe:2.3:a:sap:netweaver_abap:7.21:::::::*
sap	netweaver_abap	7.21ext	cpe:2.3:a:sap:netweaver_abap:7.21ext:::::::*
sap	netweaver_abap	7.22	cpe:2.3:a:sap:netweaver_abap:7.22:::::::*
sap	netweaver_abap	7.22ext	cpe:2.3:a:sap:netweaver_abap:7.22ext:::::::*
sap	netweaver_abap	7.49	cpe:2.3:a:sap:netweaver_abap:7.49:::::::*
sap	netweaver_abap	7.53	cpe:2.3:a:sap:netweaver_abap:7.53:::::::*
sap	netweaver_abap	7.77	cpe:2.3:a:sap:netweaver_abap:7.77:::::::*
sap	netweaver_abap	7.81	cpe:2.3:a:sap:netweaver_abap:7.81:::::::*
sap	netweaver_abap	kernel_8.04	cpe:2.3:a:sap:netweaver_abap:kernel_8.04:::::::*
sap	netweaver_abap	krnl32nuc_7.21	cpe:2.3:a:sap:netweaver_abap:krnl32nuc_7.21:::::::*
sap	netweaver_abap	krnl32uc_7.21	cpe:2.3:a:sap:netweaver_abap:krnl32uc_7.21:::::::*
sap	netweaver_abap	krnl64nuc_7.21	cpe:2.3:a:sap:netweaver_abap:krnl64nuc_7.21:::::::*
sap	netweaver_abap	krnl64uc_8.04	cpe:2.3:a:sap:netweaver_abap:krnl64uc_8.04:::::::*
sap	netweaver_application_server_abap	7.21	cpe:2.3:a:sap:netweaver_application_server_abap:7.21:::::::*
sap	netweaver_application_server_abap	7.21ext	cpe:2.3:a:sap:netweaver_application_server_abap:7.21ext:::::::*
sap	netweaver_application_server_abap	7.22	cpe:2.3:a:sap:netweaver_application_server_abap:7.22:::::::*
sap	netweaver_application_server_abap	7.22ext	cpe:2.3:a:sap:netweaver_application_server_abap:7.22ext:::::::*
sap	netweaver_application_server_abap	7.49	cpe:2.3:a:sap:netweaver_application_server_abap:7.49:::::::*
sap	netweaver_application_server_abap	7.53	cpe:2.3:a:sap:netweaver_application_server_abap:7.53:::::::*
sap	netweaver_application_server_abap	7.77	cpe:2.3:a:sap:netweaver_application_server_abap:7.77:::::::*
sap	netweaver_application_server_abap	7.81	cpe:2.3:a:sap:netweaver_application_server_abap:7.81:::::::*
sap	netweaver_application_server_abap	kernel_8.04	cpe:2.3:a:sap:netweaver_application_server_abap:kernel_8.04:::::::*
sap	netweaver_application_server_abap	krnl32nuc_7.21	cpe:2.3:a:sap:netweaver_application_server_abap:krnl32nuc_7.21:::::::*
sap	netweaver_application_server_abap	krnl32uc_7.21	cpe:2.3:a:sap:netweaver_application_server_abap:krnl32uc_7.21:::::::*
sap	netweaver_application_server_abap	krnl64nuc_7.21	cpe:2.3:a:sap:netweaver_application_server_abap:krnl64nuc_7.21:::::::*
sap	netweaver_application_server_abap	krnl64uc_8.04	cpe:2.3:a:sap:netweaver_application_server_abap:krnl64uc_8.04:::::::*

References for CVE-2021-33684

URL	Tags
https://launchpad.support.sap.com/#/notes/3032624	Permissions Required
https://wiki.scn.sap.com/wiki/pages/viewpage.action?pageId=580617506	Vendor Advisory

URL

CVE-2021-33684

Exploit prediction scoring system (EPSS) score for CVE-2021-33684

Common vulnerability scoring system (CVSS) metrics for CVE-2021-33684

Weakness enumeration for CVE-2021-33684

Affected software / configurations for CVE-2021-33684

References for CVE-2021-33684