CVE-2019-1923 [Medium] | Input Validation Bypass in Spa501g Firmware

A vulnerability in Cisco Small Business SPA500 Series IP Phones could allow a physically proximate attacker to execute arbitrary commands on the device. The vulnerability is due to improper input validation in the device configuration interface. An attacker could exploit this vulnerability by accessing the configuration interface, which may require a password, and then accessing the device's physical interface and inserting a USB storage device. A successful exploit could allow the attacker to execute arbitrary commands on the device in an elevated security context. At the time of publication, this vulnerability affected Cisco Small Business SPA500 Series IP Phones firmware releases 7.6.2SR5 and prior.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-06-15	0.21%	0.47%	+0.27%
2	2025-03-30	0.27%	0.21%	-0.06%
3	2025-03-29	—	0.27%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-06-15

0.21%

0.47%

+0.27%

2025-03-30

0.27%

0.21%

-0.06%

2025-03-29

—

0.27%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
6.6	3.1	MEDIUM	`CVSS:3.1/AV:P/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H` Click to expand Attack vector (AV:P) Hands-on access—USB, keyboard, opening the case—not something you do purely over the wire. 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.	0.7	5.9	[email protected]
6.6	3.0	MEDIUM	`CVSS:3.0/AV:P/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H` Click to expand Attack vector (AV:P) Hands-on access—USB, keyboard, opening the case—not something you do purely over the wire. 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.	0.7	5.9	[email protected]
4.6	2.0	MEDIUM	`AV:L/AC:L/Au:N/C:P/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:P) Partial confidentiality impact. Integrity impact (I:P) Partial integrity impact. Availability impact (A:P) Partial availability impact.	3.9	6.4	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

6.6

3.1

MEDIUM

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

Attack vector (AV:P): Hands-on access—USB, keyboard, opening the case—not something you do purely over the wire.
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.

0.7

5.9

[email protected]

6.6

3.0

MEDIUM

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

Attack vector (AV:P): Hands-on access—USB, keyboard, opening the case—not something you do purely over the wire.
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.

0.7

5.9

[email protected]

4.6

2.0

MEDIUM

AV:L/AC:L/Au:N/C:P/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:P): Partial confidentiality impact.
Integrity impact (I:P): Partial integrity impact.
Availability impact (A:P): Partial availability impact.

3.9

6.4

[email protected]

Affected software / configurations for CVE-2019-1923

Vendor	Product	Version	Raw CPE
cisco	spa501g_firmware	<= 7.6.2sr5	cpe:2.3:o:cisco:spa501g_firmware::::::::
cisco	spa502g_firmware	<= 7.6.2sr5	cpe:2.3:o:cisco:spa502g_firmware::::::::
cisco	spa504g_firmware	<= 7.6.2sr5	cpe:2.3:o:cisco:spa504g_firmware::::::::
cisco	spa508g_firmware	<= 7.6.2sr5	cpe:2.3:o:cisco:spa508g_firmware::::::::
cisco	spa509g_firmware	<= 7.6.2sr5	cpe:2.3:o:cisco:spa509g_firmware::::::::
cisco	spa512g_firmware	<= 7.6.2sr5	cpe:2.3:o:cisco:spa512g_firmware::::::::
cisco	spa514g_firmware	<= 7.6.2sr5	cpe:2.3:o:cisco:spa514g_firmware::::::::
cisco	spa525g2_firmware	<= 7.6.2sr5	cpe:2.3:o:cisco:spa525g2_firmware::::::::
cisco	spa500s_firmware	<= 7.6.2sr5	cpe:2.3:o:cisco:spa500s_firmware::::::::
cisco	spa500ds_firmware	<= 7.6.2sr5	cpe:2.3:o:cisco:spa500ds_firmware::::::::

References for CVE-2019-1923

URL	Tags
http://www.securityfocus.com/bid/109294	Third Party Advisory VDB Entry
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190717-spa500-command	Vendor Advisory

URL

CVE-2019-1923 | Cisco Small Business SPA500 Series IP Phones Local Command Execution Vulnerability

Exploit prediction scoring system (EPSS) score for CVE-2019-1923

Common vulnerability scoring system (CVSS) metrics for CVE-2019-1923

Weakness enumeration for CVE-2019-1923

Affected software / configurations for CVE-2019-1923

References for CVE-2019-1923