How severe is CVE-2020-27134?

CVE-2020-27134 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-2020-27134 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (74th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-27134?

CVE-2020-27134 primarily affects Cisco Jabber. In total, 12 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-27134?

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-2020-27134 published?

CVE-2020-27134 was published on 2020-12-11 and last updated on 2026-06-17.

CVE-2020-27134

CVE-2020-27134 is a critical-severity vulnerability in Cisco Jabber with a CVSS 3.x base score of 9.9. 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-200.

Key facts

Severity: Critical (CVSS 3.x base score 9.9)
CVSS v2: 9.0
EPSS exploit prediction: 2% (74th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-200
Affected product: Cisco Jabber
Published: 2020-12-11
Last modified: 2026-06-17

Description

Multiple vulnerabilities in Cisco Jabber for Windows, Jabber for MacOS, and Jabber for mobile platforms could allow an attacker to execute arbitrary programs on the underlying operating system (OS) with elevated privileges or gain access to sensitive information. For more information about these vulnerabilities, see the Details section of this advisory.

Frequently asked questions

What is CVE-2020-27134?: Multiple vulnerabilities in Cisco Jabber for Windows, Jabber for MacOS, and Jabber for mobile platforms could allow an attacker to execute arbitrary programs on the underlying operating system (OS) with elevated privileges or gain access to sensitive information. For more information about these vulnerabilities, see the Details section of this advisory.
How severe is CVE-2020-27134?: CVE-2020-27134 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-2020-27134 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (74th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-27134?: CVE-2020-27134 primarily affects Cisco Jabber. In total, 12 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-27134?: 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-2020-27134 published?: CVE-2020-27134 was published on 2020-12-11 and last updated on 2026-06-17.

References

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

Affected products (12)

cpe:2.3:a:cisco:jabber:12.9\(0\):*:*:*:*:macos:*:*
cpe:2.3:a:cisco:jabber:12.9\(0\):*:*:*:*:windows:*:*
cpe:2.3:a:cisco:jabber:12.9\(1\):*:*:*:*:macos:*:*
cpe:2.3:a:cisco:jabber:12.9\(1\):*:*:*:*:windows:*:*
cpe:2.3:a:cisco:jabber:12.9\(2\):*:*:*:*:macos:*:*
cpe:2.3:a:cisco:jabber:12.9\(2\):*:*:*:*:windows:*:*
cpe:2.3:a:cisco:jabber:12.9\(3\):*:*:*:*:macos:*:*
cpe:2.3:a:cisco:jabber:12.9\(3\):*:*:*:*:windows:*:*
cpe:2.3:a:cisco:jabber_for_mobile_platforms:12.9\(0\):*:*:*:*:*:*:*
cpe:2.3:a:cisco:jabber_for_mobile_platforms:12.9\(1\):*:*:*:*:*:*:*
cpe:2.3:a:cisco:jabber_for_mobile_platforms:12.9\(2\):*:*:*:*:*:*:*
cpe:2.3:a:cisco:jabber_for_mobile_platforms:12.9\(3\):*:*:*:*:*:*:*

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