CVE-2021-1503

CVE-2021-1503 is a high-severity vulnerability in Cisco Webex Meetings Server 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

Description

A vulnerability in Cisco Webex Network Recording Player for Windows and MacOS and Cisco Webex Player for Windows and MacOS could allow an attacker to execute arbitrary code on an affected system. This vulnerability is due to insufficient validation of values in Webex recording files that are in either Advanced Recording Format (ARF) or Webex Recording Format (WRF). An attacker could exploit this vulnerability by sending a user a malicious ARF or WRF file through a link or email attachment and persuading the user to open the file with the affected software on the local system. A successful exploit could allow the attacker to execute arbitrary code on the affected system with the privileges of the targeted user.

Frequently asked questions

What is CVE-2021-1503?
A vulnerability in Cisco Webex Network Recording Player for Windows and MacOS and Cisco Webex Player for Windows and MacOS could allow an attacker to execute arbitrary code on an affected system. This vulnerability is due to insufficient validation of values in Webex recording files that are in either Advanced Recording Format (ARF) or Webex Recording Format (WRF). An attacker could exploit this vulnerability by sending a user a malicious ARF or WRF file through a link or email attachment and persuading the user to open the file with the affected software on the local system. A successful exploit could allow the attacker to execute arbitrary code on the affected system with the privileges of the targeted user.
How severe is CVE-2021-1503?
CVE-2021-1503 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-2021-1503 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (59th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-1503?
CVE-2021-1503 primarily affects Cisco Webex Meetings Server. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-1503?
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-2021-1503 published?
CVE-2021-1503 was published on 2021-06-04 and last updated on 2026-06-17.

References

Affected products (3)

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