How severe is CVE-2020-3495?

CVE-2020-3495 has a CVSS 3.x base score of 9.9, rated critical 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-2020-3495 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 62% (99th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-3495?

CVE-2020-3495 affects Cisco Jabber. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-3495?

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-2020-3495 published?

CVE-2020-3495 was published on 2020-09-04 and last updated on 2026-06-17.

CVE-2020-3495

CVE-2020-3495 is a critical-severity vulnerability in Cisco Jabber with a CVSS 3.x base score of 9.9. Its EPSS exploit-prediction score of 62% places it in the 99th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-20.

Key facts

Severity: Critical (CVSS 3.x base score 9.9)
CVSS v2: 9.0
EPSS exploit prediction: 62% (99th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cisco Jabber
Published: 2020-09-04
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2020-3495?: 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.
How severe is CVE-2020-3495?: CVE-2020-3495 has a CVSS 3.x base score of 9.9, rated critical 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-2020-3495 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 62% (99th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-3495?: CVE-2020-3495 affects Cisco Jabber. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-3495?: 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-2020-3495 published?: CVE-2020-3495 was published on 2020-09-04 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-jabber-UyTKCPGg

Affected products (1)

cpe:2.3:a:cisco:jabber:*:*:*:*:*:windows:*:*

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