CVE-2023-20218

A vulnerability in web-based management interface of Cisco SPA500 Series Analog Telephone Adapters (ATAs) could allow an authenticated, remote attacker to to modify a web page in the context of a user's browser. This vulnerability is due to insufficient validation of user-supplied input by the web-based management interface of the affected software. An attacker could exploit this vulnerability by persuading a user to click a crafted link. A successful exploit could allow the attacker to alter the contents of a web page to redirect the user to potentially malicious websites, or the attacker could use this vulnerability to conduct further client-side attacks. Cisco will not release software updates that address this vulnerability. {{value}} ["%7b%7bvalue%7d%7d"])}]]

Published: 2023-08-03 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2023-20218 is rated Low Risk (33.4/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.37%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2023-20218

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.10% 0.37% +0.27%
2 2025-11-21 0.17% 0.10% -0.07%
3 2025-11-18 0.17%

Full EPSS history (5 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-20218

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.8 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N 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:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
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:N)
Service keeps running; no real outage angle.
3.9 1.4 [email protected]
6.1 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N 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:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
2.8 2.7 [email protected]

Weakness enumeration for CVE-2023-20218

Affected software / configurations for CVE-2023-20218

Vendor Product Version Raw CPE
cisco spa500ds_firmware cpe:2.3:o:cisco:spa500ds_firmware:-:*:*:*:*:*:*:*
cisco spa500s_firmware cpe:2.3:o:cisco:spa500s_firmware:-:*:*:*:*:*:*:*
cisco spa501g_firmware cpe:2.3:o:cisco:spa501g_firmware:-:*:*:*:*:*:*:*
cisco spa502g_firmware cpe:2.3:o:cisco:spa502g_firmware:-:*:*:*:*:*:*:*
cisco spa504g_firmware cpe:2.3:o:cisco:spa504g_firmware:-:*:*:*:*:*:*:*
cisco spa508g_firmware cpe:2.3:o:cisco:spa508g_firmware:-:*:*:*:*:*:*:*
cisco spa509g_firmware cpe:2.3:o:cisco:spa509g_firmware:-:*:*:*:*:*:*:*
cisco spa512g_firmware cpe:2.3:o:cisco:spa512g_firmware:-:*:*:*:*:*:*:*
cisco spa514g_firmware cpe:2.3:o:cisco:spa514g_firmware:-:*:*:*:*:*:*:*
cisco spa525_firmware cpe:2.3:o:cisco:spa525_firmware:-:*:*:*:*:*:*:*
cisco spa525g_firmware cpe:2.3:o:cisco:spa525g_firmware:-:*:*:*:*:*:*:*
cisco spa525g2_firmware cpe:2.3:o:cisco:spa525g2_firmware:-:*:*:*:*:*:*:*

References for CVE-2023-20218

cvelogic Threat Intelligence