CVE-2019-18863

A key length vulnerability in the implementation of the SRTP 128-bit key on Mitel 6800 and 6900 SIP series phones, versions 5.1.0.2051 SP2 and earlier, could allow an attacker to launch a man-in-the-middle attack when SRTP is used in a call. A successful exploit may allow the attacker to intercept sensitive information.

Published: 2020-03-02 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2019-18863 is rated Low Risk (37.8/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.51%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2019-18863

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.13% 0.51% +0.39%
2 2023-03-07 0.89% 0.13% -0.76%
3 2022-04-01 — 0.89% —

Full EPSS history (6 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2019-18863

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.9 3.1 MEDIUM
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 2.2 3.6 [email protected]
4.3 2.0 MEDIUM
AV:N/AC:M/Au:N/C:P/I:N/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:N)
No availability impact.
 8.6 2.9 [email protected]

Weakness enumeration for CVE-2019-18863

Affected software / configurations for CVE-2019-18863

Vendor Product Version Raw CPE
mitel 6863i_firmware < 5.1.0.2051 cpe:2.3:o:mitel:6863i_firmware:*:*:*:*:*:*:*:*
mitel 6863i_firmware 5.1.0.2051 cpe:2.3:o:mitel:6863i_firmware:5.1.0.2051:-:*:*:*:*:*:*
mitel 6863i_firmware 5.1.0.2051 cpe:2.3:o:mitel:6863i_firmware:5.1.0.2051:sp2_hf2:*:*:*:*:*:*
mitel 6865i_firmware < 5.1.0.2051 cpe:2.3:o:mitel:6865i_firmware:*:*:*:*:*:*:*:*
mitel 6865i_firmware 5.1.0.2051 cpe:2.3:o:mitel:6865i_firmware:5.1.0.2051:-:*:*:*:*:*:*
mitel 6865i_firmware 5.1.0.2051 cpe:2.3:o:mitel:6865i_firmware:5.1.0.2051:sp2_hf2:*:*:*:*:*:*
mitel 6867i_firmware < 5.1.0.2051 cpe:2.3:o:mitel:6867i_firmware:*:*:*:*:*:*:*:*
mitel 6867i_firmware 5.1.0.2051 cpe:2.3:o:mitel:6867i_firmware:5.1.0.2051:-:*:*:*:*:*:*
mitel 6867i_firmware 5.1.0.2051 cpe:2.3:o:mitel:6867i_firmware:5.1.0.2051:sp2_hf2:*:*:*:*:*:*
mitel 6869i_firmware < 5.1.0.2051 cpe:2.3:o:mitel:6869i_firmware:*:*:*:*:*:*:*:*
mitel 6869i_firmware 5.1.0.2051 cpe:2.3:o:mitel:6869i_firmware:5.1.0.2051:-:*:*:*:*:*:*
mitel 6869i_firmware 5.1.0.2051 cpe:2.3:o:mitel:6869i_firmware:5.1.0.2051:sp2_hf2:*:*:*:*:*:*
mitel 6873i_firmware < 5.1.0.2051 cpe:2.3:o:mitel:6873i_firmware:*:*:*:*:*:*:*:*
mitel 6873i_firmware 5.1.0.2051 cpe:2.3:o:mitel:6873i_firmware:5.1.0.2051:-:*:*:*:*:*:*
mitel 6873i_firmware 5.1.0.2051 cpe:2.3:o:mitel:6873i_firmware:5.1.0.2051:sp2_hf2:*:*:*:*:*:*
mitel 6920_firmware < 5.1.0.2051 cpe:2.3:o:mitel:6920_firmware:*:*:*:*:*:*:*:*
mitel 6920_firmware 5.1.0.2051 cpe:2.3:o:mitel:6920_firmware:5.1.0.2051:-:*:*:*:*:*:*
mitel 6920_firmware 5.1.0.2051 cpe:2.3:o:mitel:6920_firmware:5.1.0.2051:sp2_hf2:*:*:*:*:*:*
mitel 6930_firmware < 5.1.0.2051 cpe:2.3:o:mitel:6930_firmware:*:*:*:*:*:*:*:*
mitel 6930_firmware 5.1.0.2051 cpe:2.3:o:mitel:6930_firmware:5.1.0.2051:-:*:*:*:*:*:*
mitel 6930_firmware 5.1.0.2051 cpe:2.3:o:mitel:6930_firmware:5.1.0.2051:sp2_hf2:*:*:*:*:*:*
mitel 6940_firmware < 5.1.0.2051 cpe:2.3:o:mitel:6940_firmware:*:*:*:*:*:*:*:*
mitel 6940_firmware 5.1.0.2051 cpe:2.3:o:mitel:6940_firmware:5.1.0.2051:-:*:*:*:*:*:*
mitel 6940_firmware 5.1.0.2051 cpe:2.3:o:mitel:6940_firmware:5.1.0.2051:sp2_hf2:*:*:*:*:*:*

References for CVE-2019-18863

cvelogic Threat Intelligence