How severe is CVE-2020-13617?

CVE-2020-13617 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2020-13617 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-13617?

CVE-2020-13617 primarily affects Mitel 6863 Firmware. In total, 66 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-13617?

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-2020-13617 published?

CVE-2020-13617 was published on 2020-08-26 and last updated on 2026-06-17.

CVE-2020-13617

CVE-2020-13617 is a high-severity vulnerability in Mitel 6863 Firmware with a CVSS 3.x base score of 7.5. 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-307.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (68th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-307
Affected product: Mitel 6863 Firmware
Published: 2020-08-26
Last modified: 2026-06-17

Description

The Web UI component of Mitel MiVoice 6800 and 6900 series SIP Phones with firmware before 5.1.0.SP5 could allow an unauthenticated attacker to expose sensitive information due to improper memory handling during failed login attempts.

Frequently asked questions

What is CVE-2020-13617?: The Web UI component of Mitel MiVoice 6800 and 6900 series SIP Phones with firmware before 5.1.0.SP5 could allow an unauthenticated attacker to expose sensitive information due to improper memory handling during failed login attempts.
How severe is CVE-2020-13617?: CVE-2020-13617 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2020-13617 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-13617?: CVE-2020-13617 primarily affects Mitel 6863 Firmware. In total, 66 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-13617?: 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-2020-13617 published?: CVE-2020-13617 was published on 2020-08-26 and last updated on 2026-06-17.

References

Affected products (66)

cpe:2.3:o:mitel:6863_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitel:6863_firmware:5.1:-:*:*:*:*:*:*
cpe:2.3:o:mitel:6863_firmware:5.1:sp1:*:*:*:*:*:*
cpe:2.3:o:mitel:6863_firmware:5.1:sp2:*:*:*:*:*:*
cpe:2.3:o:mitel:6863_firmware:5.1:sp3:*:*:*:*:*:*
cpe:2.3:o:mitel:6863_firmware:5.1:sp4:*:*:*:*:*:*
cpe:2.3:o:mitel:6865_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitel:6865_firmware:5.1:-:*:*:*:*:*:*
cpe:2.3:o:mitel:6865_firmware:5.1:sp1:*:*:*:*:*:*
cpe:2.3:o:mitel:6865_firmware:5.1:sp2:*:*:*:*:*:*
cpe:2.3:o:mitel:6865_firmware:5.1:sp3:*:*:*:*:*:*
cpe:2.3:o:mitel:6865_firmware:5.1:sp4:*:*:*:*:*:*
cpe:2.3:o:mitel:6867_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitel:6867_firmware:5.1:-:*:*:*:*:*:*
cpe:2.3:o:mitel:6867_firmware:5.1:sp1:*:*:*:*:*:*
cpe:2.3:o:mitel:6867_firmware:5.1:sp2:*:*:*:*:*:*
cpe:2.3:o:mitel:6867_firmware:5.1:sp3:*:*:*:*:*:*
cpe:2.3:o:mitel:6867_firmware:5.1:sp4:*:*:*:*:*:*
cpe:2.3:o:mitel:6869_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitel:6869_firmware:5.1:-:*:*:*:*:*:*
cpe:2.3:o:mitel:6869_firmware:5.1:sp1:*:*:*:*:*:*
cpe:2.3:o:mitel:6869_firmware:5.1:sp2:*:*:*:*:*:*
cpe:2.3:o:mitel:6869_firmware:5.1:sp3:*:*:*:*:*:*
cpe:2.3:o:mitel:6869_firmware:5.1:sp4:*:*:*:*:*:*
cpe:2.3:o:mitel:6873_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitel:6873_firmware:5.1:-:*:*:*:*:*:*
cpe:2.3:o:mitel:6873_firmware:5.1:sp1:*:*:*:*:*:*
cpe:2.3:o:mitel:6873_firmware:5.1:sp2:*:*:*:*:*:*
cpe:2.3:o:mitel:6873_firmware:5.1:sp3:*:*:*:*:*:*
cpe:2.3:o:mitel:6873_firmware:5.1:sp4:*:*:*:*:*:*
cpe:2.3:o:mitel:6940_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitel:6940_firmware:5.1:-:*:*:*:*:*:*
cpe:2.3:o:mitel:6940_firmware:5.1:sp1:*:*:*:*:*:*
cpe:2.3:o:mitel:6940_firmware:5.1:sp2:*:*:*:*:*:*
cpe:2.3:o:mitel:6940_firmware:5.1:sp3:*:*:*:*:*:*
cpe:2.3:o:mitel:6940_firmware:5.1:sp4:*:*:*:*:*:*
cpe:2.3:o:mitel:6970_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitel:6970_firmware:5.1:-:*:*:*:*:*:*
cpe:2.3:o:mitel:6970_firmware:5.1:sp1:*:*:*:*:*:*
cpe:2.3:o:mitel:6970_firmware:5.1:sp2:*:*:*:*:*:*

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