CVE-2020-12456
CVE-2020-12456 is a high-severity vulnerability in Mitel Mivoice Connect Client with a CVSS 3.x base score of 8.8. 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-22.
Key facts
- Severity: High (CVSS 3.x base score 8.8)
- CVSS v2: 6.5
- EPSS exploit prediction: 3% (86th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-22
- Affected product: Mitel Mivoice Connect Client
- Published:
- Last modified:
Description
A remote code execution vulnerability in Mitel MiVoice Connect Client before 214.100.1223.0 could allow an attacker to execute arbitrary code in the chat notification window, due to improper rendering of chat messages. A successful exploit could allow an attacker to steal session cookies, perform directory traversal, and execute arbitrary scripts in the context of the Connect client.
Frequently asked questions
- What is CVE-2020-12456?
- A remote code execution vulnerability in Mitel MiVoice Connect Client before 214.100.1223.0 could allow an attacker to execute arbitrary code in the chat notification window, due to improper rendering of chat messages. A successful exploit could allow an attacker to steal session cookies, perform directory traversal, and execute arbitrary scripts in the context of the Connect client.
- How severe is CVE-2020-12456?
- CVE-2020-12456 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2020-12456 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2020-12456?
- CVE-2020-12456 affects Mitel Mivoice Connect Client. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2020-12456?
- 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-2020-12456 published?
- CVE-2020-12456 was published on 2020-08-26 and last updated on 2026-06-17.
References
- https://www.mitel.com/support/security-advisories
- https://www.mitel.com/support/security-advisories/mitel-product-security-advisory-20-0006
Affected products (1)
- cpe:2.3:a:mitel:mivoice_connect_client:*:*:*:*:*:*:*:*
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