CVE-2020-3495 | Cisco Jabber for Windows Message Handling Arbitrary Code Execution Vulnerability

A vulnerability in Cisco Jabber for Windows could allow an authenticated, remote attacker to execute arbitrary code. The vulnerability is due to improper validation of message contents. An attacker could exploit this vulnerability by sending specially crafted Extensible Messaging and Presence Protocol (XMPP) messages to the affected software. A successful exploit could allow the attacker to cause the application to execute arbitrary programs on the targeted system with the privileges of the user account that is running the Cisco Jabber client software, possibly resulting in arbitrary code execution.

Published: 2020-09-03 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2020-3495 is rated High Risk (79.3/100): CVSS Critical severity, with high exploitation likelihood (EPSS 61.86%, 99th percentile). EPSS ranks this CVE among the most likely to be exploited in the near term. EPSS rose +57.46% over the last day, indicating growing attacker interest. High exploitation likelihood—assess exposure and prioritize remediation.

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-2020-3495

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 4.40% 61.86% +57.46%
2 2026-06-02 4.77% 4.40% -0.37%
3 2026-05-22 — 4.77% —

Full EPSS history (20 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-3495

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.9 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H 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:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.1 6.0 [email protected]
8.8 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H 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:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
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:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.8 5.9 [email protected]
9.0 2.0 HIGH
AV:N/AC:L/Au:S/C:C/I:C/A:C Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:S)
A single authentication is required.
Confidentiality impact (C:C)
Complete confidentiality impact.
Integrity impact (I:C)
Complete integrity impact.
Availability impact (A:C)
Complete availability impact.
 8.0 10.0 [email protected]

Weakness enumeration for CVE-2020-3495

Affected software / configurations for CVE-2020-3495

Vendor Product Version Raw CPE
cisco jabber >= 12.1, < 12.1.3 cpe:2.3:a:cisco:jabber:*:*:*:*:*:windows:*:*
cisco jabber >= 12.5, < 12.5.2 cpe:2.3:a:cisco:jabber:*:*:*:*:*:windows:*:*
cisco jabber >= 12.6, < 12.6.3 cpe:2.3:a:cisco:jabber:*:*:*:*:*:windows:*:*
cisco jabber >= 12.7, < 12.7.2 cpe:2.3:a:cisco:jabber:*:*:*:*:*:windows:*:*
cisco jabber >= 12.8, < 12.8.3 cpe:2.3:a:cisco:jabber:*:*:*:*:*:windows:*:*
cisco jabber >= 12.9, < 12.9.1 cpe:2.3:a:cisco:jabber:*:*:*:*:*:windows:*:*

References for CVE-2020-3495

cvelogic Threat Intelligence