How severe is CVE-2023-20018?

CVE-2023-20018 has a CVSS 3.x base score of 8.6, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability high.

Is CVE-2023-20018 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (45th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-20018?

CVE-2023-20018 primarily affects Cisco Ip Phone 7800 Firmware. In total, 22 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-20018?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2023-20018 published?

CVE-2023-20018 was published on 2023-01-20 and last updated on 2026-06-17.

CVE-2023-20018

CVE-2023-20018 is a high-severity vulnerability in Cisco Ip Phone 7800 Firmware with a CVSS 3.x base score of 8.6. 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-863.

Key facts

Severity: High (CVSS 3.x base score 8.6)
EPSS exploit prediction: 1% (45th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-863
Affected product: Cisco Ip Phone 7800 Firmware
Published: 2023-01-20
Last modified: 2026-06-17

Description

A vulnerability in the web-based management interface of Cisco IP Phone 7800 and 8800 Series Phones could allow an unauthenticated, remote attacker to bypass authentication on an affected device. This vulnerability is due to insufficient validation of user-supplied input. An attacker could exploit this vulnerability by sending a crafted request to the web-based management interface. A successful exploit could allow the attacker to access certain parts of the web interface that would normally require authentication.

Frequently asked questions

What is CVE-2023-20018?: A vulnerability in the web-based management interface of Cisco IP Phone 7800 and 8800 Series Phones could allow an unauthenticated, remote attacker to bypass authentication on an affected device. This vulnerability is due to insufficient validation of user-supplied input. An attacker could exploit this vulnerability by sending a crafted request to the web-based management interface. A successful exploit could allow the attacker to access certain parts of the web interface that would normally require authentication.
How severe is CVE-2023-20018?: CVE-2023-20018 has a CVSS 3.x base score of 8.6, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability high.
Is CVE-2023-20018 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (45th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-20018?: CVE-2023-20018 primarily affects Cisco Ip Phone 7800 Firmware. In total, 22 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-20018?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2023-20018 published?: CVE-2023-20018 was published on 2023-01-20 and last updated on 2026-06-17.

References

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ip-phone-auth-bypass-pSqxZRPR

Affected products (22)

cpe:2.3:o:cisco:ip_phone_7800_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_7811_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_7821_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_7832_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_7841_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_7861_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_8800_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_8811_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_8821_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_8821-ex_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_8831_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_8832_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_8841_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_8845_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_8851_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_8861_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phone_8865_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ip_phones_8832_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:unified_ip_phone_8851nr_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:unified_ip_phone_8865nr_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:wireless_ip_phone_8821_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:wireless_ip_phone_8821-ex_firmware:*:*:*:*:*:*:*:*

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