How severe is CVE-2023-20126?

CVE-2023-20126 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2023-20126 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 38% (98th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-20126?

CVE-2023-20126 affects Cisco Spa112 Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-20126?

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

When was CVE-2023-20126 published?

CVE-2023-20126 was published on 2023-05-04 and last updated on 2026-06-17.

CVE-2023-20126

CVE-2023-20126 is a critical-severity vulnerability in Cisco Spa112 Firmware with a CVSS 3.x base score of 9.8. Its EPSS exploit-prediction score of 38% places it in the 98th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-306.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 38% (98th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-306
Affected product: Cisco Spa112 Firmware
Published: 2023-05-04
Last modified: 2026-06-17

Description

A vulnerability in the web-based management interface of Cisco SPA112 2-Port Phone Adapters could allow an unauthenticated, remote attacker to execute arbitrary code on an affected device. This vulnerability is due to a missing authentication process within the firmware upgrade function. An attacker could exploit this vulnerability by upgrading an affected device to a crafted version of firmware. A successful exploit could allow the attacker to execute arbitrary code on the affected device with full privileges. Cisco has not released firmware updates to address this vulnerability.

Frequently asked questions

What is CVE-2023-20126?: A vulnerability in the web-based management interface of Cisco SPA112 2-Port Phone Adapters could allow an unauthenticated, remote attacker to execute arbitrary code on an affected device. This vulnerability is due to a missing authentication process within the firmware upgrade function. An attacker could exploit this vulnerability by upgrading an affected device to a crafted version of firmware. A successful exploit could allow the attacker to execute arbitrary code on the affected device with full privileges. Cisco has not released firmware updates to address this vulnerability.
How severe is CVE-2023-20126?: CVE-2023-20126 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2023-20126 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 38% (98th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-20126?: CVE-2023-20126 affects Cisco Spa112 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-20126?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2023-20126 published?: CVE-2023-20126 was published on 2023-05-04 and last updated on 2026-06-17.

References

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-spa-unauth-upgrade-UqhyTWW

Affected products (1)

cpe:2.3:o:cisco:spa112_firmware:1.4.1:sr9:*:*:*:*:*:*

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