CVE-2020-15632 [High] | Security Bypass in Dir-842 Firmware

This vulnerability allows network-adjacent attackers to bypass authentication on affected installations of D-Link DIR-842 3.13B05 routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within the processing of HNAP GetCAPTCHAsetting requests. The issue results from the lack of proper handling of sessions. An attacker can leverage this vulnerability to execute arbitrary code in the context of the device. Was ZDI-CAN-10083.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-06-15	4.20%	3.32%	-0.88%
2	2025-03-30	11.44%	4.20%	-7.24%
3	2025-03-29	—	11.44%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-06-15

4.20%

3.32%

-0.88%

2025-03-30

11.44%

4.20%

-7.24%

2025-03-29

—

11.44%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
8.8	3.1	HIGH	`CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/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: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: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.	2.8	5.9	[email protected]
8.8	3.0	HIGH	`CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/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: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: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.	2.8	5.9	[email protected]
5.8	2.0	MEDIUM	`AV:A/AC:L/Au:N/C:P/I:P/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:N) No authentication is required. Confidentiality impact (C:P) Partial confidentiality impact. Integrity impact (I:P) Partial integrity impact. Availability impact (A:P) Partial availability impact.	6.5	6.4	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

8.8

3.1

HIGH

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

2.8

5.9

[email protected]

8.8

3.0

HIGH

CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/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: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: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.

2.8

5.9

[email protected]

5.8

2.0

MEDIUM

AV:A/AC:L/Au:N/C:P/I:P/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:N): No authentication is required.
Confidentiality impact (C:P): Partial confidentiality impact.
Integrity impact (I:P): Partial integrity impact.
Availability impact (A:P): Partial availability impact.

6.5

6.4

[email protected]

Affected software / configurations for CVE-2020-15632

Vendor	Product	Version	Raw CPE
dlink	dir-842_firmware	<= 3.13b09	cpe:2.3:o:dlink:dir-842_firmware::::::::

References for CVE-2020-15632

URL	Tags
https://supportannouncement.us.dlink.com/announcement/publication.aspx?name=SAP10184	Patch Vendor Advisory
https://www.zerodayinitiative.com/advisories/ZDI-20-880/	Third Party Advisory VDB Entry

URL

CVE-2020-15632

Exploit prediction scoring system (EPSS) score for CVE-2020-15632

Common vulnerability scoring system (CVSS) metrics for CVE-2020-15632

Weakness enumeration for CVE-2020-15632

Affected software / configurations for CVE-2020-15632

References for CVE-2020-15632