CVE-2021-1527 | Cisco Webex Player Memory Corruption Vulnerability

A vulnerability in Cisco Webex Player for Windows and MacOS could allow an attacker to cause the affected software to terminate or to gain access to memory state information that is related to the vulnerable application. The vulnerability is due to insufficient validation of values in Webex recording files that are stored in Webex Recording Format (WRF). An attacker could exploit this vulnerability by sending a malicious WRF file to a user as a link or email attachment and then persuading the user to open the file with the affected software on the local system. A successful exploit could allow the attacker to crash the affected software and view memory state information.

Published: 2021-06-04 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-1527 is rated Low Risk (36.2/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.58%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

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-2021-1527

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 0.54% 0.58% +0.04%
2 2026-01-25 0.27% 0.54% +0.27%
3 2025-03-17 — 0.27% —

Full EPSS history (8 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-1527

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.3 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
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:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
 1.8 3.4 [email protected]
6.1 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
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:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.8 4.2 [email protected]
5.8 2.0 MEDIUM
AV:N/AC:M/Au:N/C:P/I:N/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:P)
Partial availability impact.
 8.6 4.9 [email protected]

Weakness enumeration for CVE-2021-1527

Affected software / configurations for CVE-2021-1527

Vendor Product Version Raw CPE
cisco webex_player < 41.5 cpe:2.3:a:cisco:webex_player:*:*:*:*:*:macos:*:*
cisco webex_player < 41.5 cpe:2.3:a:cisco:webex_player:*:*:*:*:*:windows:*:*

References for CVE-2021-1527

cvelogic Threat Intelligence