How severe is CVE-2025-20351?

CVE-2025-20351 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2025-20351 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (18th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-20351?

CVE-2025-20351 primarily affects Cisco Desk Phone 9871 Firmware. In total, 67 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2025-20351?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2025-20351 have an EU (EUVD) identifier?

Yes. CVE-2025-20351 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-34666.

When was CVE-2025-20351 published?

CVE-2025-20351 was published on 2025-10-15 and last updated on 2026-06-17.

CVE-2025-20351

CVE-2025-20351 is a medium-severity vulnerability in Cisco Desk Phone 9871 Firmware with a CVSS 3.x base score of 6.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-79.

Key facts

Severity: Medium (CVSS 3.x base score 6.1)
EPSS exploit prediction: 0% (18th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-34666
Weakness: CWE-79
Affected product: Cisco Desk Phone 9871 Firmware
Published: 2025-10-15
Last modified: 2026-06-17

Description

A vulnerability in the web UI of Cisco Desk Phone 9800 Series, Cisco IP Phone 7800 and 8800 Series, and Cisco Video Phone 8875 running Cisco SIP Software could allow an unauthenticated, remote attacker to conduct XSS attacks against a user of the web UI. This vulnerability exists because the web UI of an affected device does not sufficiently validate user-supplied input. An attacker could exploit this vulnerability by persuading a user to click a crafted link. A successful exploit could allow the attacker to execute arbitrary script code in the context of the affected interface or access sensitive, browser-based information. Note: To exploit this vulnerability, the phone must be registered to Cisco Unified Communications Manager and have Web Access enabled. Web Access is disabled by default.

Frequently asked questions

What is CVE-2025-20351?: A vulnerability in the web UI of Cisco Desk Phone 9800 Series, Cisco IP Phone 7800 and 8800 Series, and Cisco Video Phone 8875 running Cisco SIP Software could allow an unauthenticated, remote attacker to conduct XSS attacks against a user of the web UI. This vulnerability exists because the web UI of an affected device does not sufficiently validate user-supplied input. An attacker could exploit this vulnerability by persuading a user to click a crafted link. A successful exploit could allow the attacker to execute arbitrary script code in the context of the affected interface or access sensitive, browser-based information. Note: To exploit this vulnerability, the phone must be registered to Cisco Unified Communications Manager and have Web Access enabled. Web Access is disabled by default.
How severe is CVE-2025-20351?: CVE-2025-20351 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2025-20351 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (18th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-20351?: CVE-2025-20351 primarily affects Cisco Desk Phone 9871 Firmware. In total, 67 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-20351?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-20351 have an EU (EUVD) identifier?: Yes. CVE-2025-20351 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-34666.
When was CVE-2025-20351 published?: CVE-2025-20351 was published on 2025-10-15 and last updated on 2026-06-17.

References

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-phone-dos-FPyjLV7A

Affected products (67)

cpe:2.3:o:cisco:desk_phone_9871_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:desk_phone_9841_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:desk_phone_9851_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:desk_phone_9861_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_8865_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_8865_firmware:14.3\(1\):*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_8865_firmware:14.3\(1\):sr1:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_7811_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_7811_firmware:14.3\(1\):*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_7811_firmware:14.3\(1\):sr1:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_7821_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_7821_firmware:14.3\(1\):*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_7821_firmware:14.3\(1\):sr1:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_7841_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_7841_firmware:14.3\(1\):*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_7841_firmware:14.3\(1\):sr1:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_7861_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_7861_firmware:14.3\(1\):*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_7861_firmware:14.3\(1\):sr1:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_8811_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_8811_firmware:14.3\(1\):*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_8811_firmware:14.3\(1\):sr1:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_8832_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_8832_firmware:14.3\(1\):*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_8832_firmware:14.3\(1\):sr1:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_8841_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_8841_firmware:14.3\(1\):*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_8841_firmware:14.3\(1\):sr1:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_8845_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_8845_firmware:14.3\(1\):*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_8845_firmware:14.3\(1\):sr1:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_8851_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_8851_firmware:14.3\(1\):*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_8851_firmware:14.3\(1\):sr1:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_8861_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_8861_firmware:14.3\(1\):*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_8861_firmware:14.3\(1\):sr1:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_8821_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_8821_firmware:11.0\(0.7\):mpp:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_8821_firmware:11.0\(1\):*:*:*:*:*:*:*

More vulnerabilities in Cisco Desk Phone 9871 Firmware

CVE-2025-20350 — High (CVSS 7.5): A vulnerability in the web UI of Cisco Desk Phone 9800 Series, Cisco IP Phone 7800 and 8800 Series, and Cisco Video…
CVE-2025-20336 — Medium (CVSS 5.3): A vulnerability in the directory permissions of Cisco Desk Phone 9800 Series, Cisco IP Phone 7800 and 8800 Series, and…
CVE-2025-20335 — Medium (CVSS 5.3): A vulnerability in the directory permissions of Cisco Desk Phone 9800 Series, Cisco IP Phone 7800 and 8800 Series, and…
CVE-2024-20445 — Medium (CVSS 5.3): A vulnerability in the web UI of Cisco Desk Phone 9800 Series, Cisco IP Phone 7800 and 8800 Series, and Cisco Video…
CVE-2025-20158 — Medium (CVSS 4.4): A vulnerability in the debug shell of Cisco Video Phone 8875 and Cisco Desk Phone 9800 Series could allow an…

All CVEs affecting Cisco Desk Phone 9871 Firmware →

Other CWE-79 (Cross-site Scripting (XSS)) vulnerabilities

CVE-2025-49410 — Critical (CVSS 10.0): Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Imran Emu TC…
CVE-2024-47875 — Critical (CVSS 10.0): DOMPurify is a DOM-only, super-fast, uber-tolerant XSS sanitizer for HTML, MathML and SVG. DOMpurify was vulnerable to…
CVE-2024-6886 — Critical (CVSS 10.0): Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in Gitea…
CVE-2023-45144 — Critical (CVSS 10.0): com.xwiki.identity-oauth:identity-oauth-ui is a package to aid in building identity and service providers based on…
CVE-2023-45138 — Critical (CVSS 10.0): Change Request is an pplication allowing users to request changes on a wiki without publishing the changes directly.…
CVE-2022-4361 — Critical (CVSS 10.0): Keycloak, an open-source identity and access management solution, has a cross-site scripting (XSS) vulnerability in the…

Browse all CWE-79 (Cross-site Scripting (XSS)) vulnerabilities →