How severe is CVE-2018-15421?

CVE-2018-15421 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2018-15421 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (79th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-15421?

CVE-2018-15421 primarily affects Cisco Webex Meetings Online. In total, 21 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-15421?

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-2018-15421 published?

CVE-2018-15421 was published on 2018-10-05 and last updated on 2026-06-17.

CVE-2018-15421

CVE-2018-15421 is a high-severity vulnerability in Cisco Webex Meetings Online with a CVSS 3.x base score of 7.8. 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-787.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v2: 9.3
EPSS exploit prediction: 2% (79th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Cisco Webex Meetings Online
Published: 2018-10-05
Last modified: 2026-06-17

Description

A vulnerability in the Cisco Webex Network Recording Player for Microsoft Windows and the Cisco Webex Player for Microsoft Windows could allow an attacker to execute arbitrary code on an affected system. The vulnerability exist because the affected software improperly validates Advanced Recording Format (ARF) and Webex Recording Format (WRF) files. An attacker could exploit this vulnerability by sending a user a malicious ARF or WRF file via a link or an email attachment and persuading the user to open the file by using the affected software. A successful exploit could allow the attacker to execute arbitrary code on the affected system.

Frequently asked questions

What is CVE-2018-15421?: A vulnerability in the Cisco Webex Network Recording Player for Microsoft Windows and the Cisco Webex Player for Microsoft Windows could allow an attacker to execute arbitrary code on an affected system. The vulnerability exist because the affected software improperly validates Advanced Recording Format (ARF) and Webex Recording Format (WRF) files. An attacker could exploit this vulnerability by sending a user a malicious ARF or WRF file via a link or an email attachment and persuading the user to open the file by using the affected software. A successful exploit could allow the attacker to execute arbitrary code on the affected system.
How severe is CVE-2018-15421?: CVE-2018-15421 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2018-15421 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (79th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-15421?: CVE-2018-15421 primarily affects Cisco Webex Meetings Online. In total, 21 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-15421?: 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-2018-15421 published?: CVE-2018-15421 was published on 2018-10-05 and last updated on 2026-06-17.

References

Affected products (21)

cpe:2.3:a:cisco:webex_meetings_online:*:*:*:*:*:*:*:*
cpe:2.3:a:cisco:webex_meetings_server:2.5:maintenance_release2_patch1:*:*:*:*:*:*
cpe:2.3:a:cisco:webex_meetings_server:2.5:maintenance_release5_patch1:*:*:*:*:*:*
cpe:2.3:a:cisco:webex_meetings_server:2.5:maintenance_release6_patch2:*:*:*:*:*:*
cpe:2.3:a:cisco:webex_meetings_server:2.5:maintenance_release6_patch3:*:*:*:*:*:*
cpe:2.3:a:cisco:webex_meetings_server:2.5:maintenance_release6_patch4:*:*:*:*:*:*
cpe:2.3:a:cisco:webex_meetings_server:2.5.1.29:*:*:*:*:*:*:*
cpe:2.3:a:cisco:webex_meetings_server:2.6:*:*:*:*:*:*:*
cpe:2.3:a:cisco:webex_meetings_server:2.6:maintenance_release1_patch1:*:*:*:*:*:*
cpe:2.3:a:cisco:webex_meetings_server:2.6:maintenance_release2_patch1:*:*:*:*:*:*
cpe:2.3:a:cisco:webex_meetings_server:2.6:maintenance_release3_patch1:*:*:*:*:*:*
cpe:2.3:a:cisco:webex_meetings_server:2.6:maintenance_release3_patch2:*:*:*:*:*:*
cpe:2.3:a:cisco:webex_meetings_server:2.7:*:*:*:*:*:*:*
cpe:2.3:a:cisco:webex_meetings_server:2.7:base:*:*:*:*:*:*
cpe:2.3:a:cisco:webex_meetings_server:2.7:maintenance_release1_patch1:*:*:*:*:*:*
cpe:2.3:a:cisco:webex_meetings_server:2.7:maintenance_release2_patch1:*:*:*:*:*:*
cpe:2.3:a:cisco:webex_meetings_server:2.7.1:*:*:*:*:*:*:*
cpe:2.3:a:cisco:webex_meetings_server:2.8:*:*:*:*:*:*:*
cpe:2.3:a:cisco:webex_meetings_server:2.8:base:*:*:*:*:*:*
cpe:2.3:a:cisco:webex_business_suite_32:*:*:*:*:*:*:*:*
cpe:2.3:a:cisco:webex_business_suite_33:*:*:*:*:*:*:*:*

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